Align instability documentation with current runtime (#74)

docs/LEGACY_INSTABILITY_AUDIT.md

@@ -1,6 +1,6 @@
 # Mystcraft Legacy instability audit (Milestone 6, issue #63)
 
-This is a behavior contract for Milestone 6, **not a completed runtime instability system**. It compares the user-provided 0.13.7.06 class files at `/home/dnorberg/Documents/mystcraft-src/mystcraft-1.12.2-0.13.7.06/` with [Mystcraft Legacy source at commit `9bc8ddc`](https://github.com/Mystcraft/Mystcraft-Legacy/tree/9bc8ddc061845df0cd5ea47f4fdef773cff786ae). Values below are source defaults, not a claim that every historical config or server used them. Rivencraft 0.5.1.0 saves a provisional writing-instability score and repaired active-page order, but has no hazard loop yet.
+This is the behavior contract used to implement Milestone 6. It compares the user-provided 0.13.7.06 class files at `/home/dnorberg/Documents/mystcraft-src/mystcraft-1.12.2-0.13.7.06/` with [Mystcraft Legacy source at commit `9bc8ddc`](https://github.com/Mystcraft/Mystcraft-Legacy/tree/9bc8ddc061845df0cd5ea47f4fdef773cff786ae). Values below are source defaults, not a claim that every historical config or server used them. Rivencraft now persists frozen writing-instability scores and provider plans and runs the implemented providers through a bounded, Age-scoped scheduler. The audit remains authoritative for Legacy behavior; the linked runtime documents identify modern adaptations and remaining gaps.
 
 ## Score, grammar, and selection in Legacy
 
@@ -35,8 +35,8 @@ These entry costs are from [`InstabilityData.initialize()`](https://github.com/M
 
 | Family | Legacy behavior | M6 disposition |
 | --- | --- | --- |
-| Player and hostile-mob potions | Local/global blindness, fatigue, hunger, nausea, poison, slowness, weakness, wither; hostile regeneration/resistance ([`EffectPotion`](https://github.com/Mystcraft/Mystcraft-Legacy/blob/9bc8ddc061845df0cd5ea47f4fdef773cff786ae/src/main/java/com/xcompwiz/mystcraft/effects/EffectPotion.java)). | Implement in #67 with server-only, Age-scoped entity targeting and rate limits. No effects in preview/snapshot worlds. |
-| Colored decay | Blue, purple, red, white providers place advancing decay and extra-tick it; black provider is commented out. Decay handlers differ in spread/consumption ([providers](https://github.com/Mystcraft/Mystcraft-Legacy/tree/9bc8ddc061845df0cd5ea47f4fdef773cff786ae/src/main/java/com/xcompwiz/mystcraft/instability/providers), [handlers](https://github.com/Mystcraft/Mystcraft-Legacy/tree/9bc8ddc061845df0cd5ea47f4fdef773cff786ae/src/main/java/com/xcompwiz/mystcraft/instability/decay)). | Implement bounded, reversible-by-admin world mutation in #68; exact 1.12 spread/update rates require adaptation and tests. Exclude protected spawn/portal areas. Black/green/yellow are **not** proven active Legacy providers. |
+| Player and hostile-mob potions | Local/global blindness, fatigue, hunger, nausea, poison, slowness, weakness, wither; hostile regeneration/resistance ([`EffectPotion`](https://github.com/Mystcraft/Mystcraft-Legacy/blob/9bc8ddc061845df0cd5ea47f4fdef773cff786ae/src/main/java/com/xcompwiz/mystcraft/effects/EffectPotion.java)). | Implemented in #67 with server-only, Age-scoped entity targeting and rate limits. No effects run in preview/snapshot worlds. |
+| Colored decay | Blue, purple, red, white providers place advancing decay and extra-tick it; black provider is commented out. Decay handlers differ in spread/consumption ([providers](https://github.com/Mystcraft/Mystcraft-Legacy/tree/9bc8ddc061845df0cd5ea47f4fdef773cff786ae/src/main/java/com/xcompwiz/mystcraft/instability/providers), [handlers](https://github.com/Mystcraft/Mystcraft-Legacy/tree/9bc8ddc061845df0cd5ea47f4fdef773cff786ae/src/main/java/com/xcompwiz/mystcraft/instability/decay)). | Implemented in #68 as bounded world mutation with protected spawn/portal areas and configurable shutdown. Black/green/yellow remain excluded because they are **not** proven active Legacy providers. |
 | Lightning and explosions | Random per-chunk strike/explosion attempts ([`EffectLightning`](https://github.com/Mystcraft/Mystcraft-Legacy/blob/9bc8ddc061845df0cd5ea47f4fdef773cff786ae/src/main/java/com/xcompwiz/mystcraft/effects/EffectLightning.java), [`EffectExplosions`](https://github.com/Mystcraft/Mystcraft-Legacy/blob/9bc8ddc061845df0cd5ea47f4fdef773cff786ae/src/main/java/com/xcompwiz/mystcraft/effects/EffectExplosions.java)). | Implemented in #69 with separate damage/fire/griefing policies and loaded-Age bounds; see `INSTABILITY_RUNTIME.md`. |
 | Meteor, scorching | Meteor entity spawn and sky-exposed entity ignition ([`EffectMeteor`](https://github.com/Mystcraft/Mystcraft-Legacy/blob/9bc8ddc061845df0cd5ea47f4fdef773cff786ae/src/main/java/com/xcompwiz/mystcraft/effects/EffectMeteor.java), [`EffectScorched`](https://github.com/Mystcraft/Mystcraft-Legacy/blob/9bc8ddc061845df0cd5ea47f4fdef773cff786ae/src/main/java/com/xcompwiz/mystcraft/effects/EffectScorched.java)). | #70 implements a bounded meteor descent/impact and the active `burning` card; see `INSTABILITY_ENVIRONMENTAL.md`. Legacy `meteor/roar.ogg` is reused. |
 | Crumble and erosion | Crumble maps blocks to weaker states; erosion spreads adjacent fluids and has extra lake-generation methods ([`EffectCrumble`](https://github.com/Mystcraft/Mystcraft-Legacy/blob/9bc8ddc061845df0cd5ea47f4fdef773cff786ae/src/main/java/com/xcompwiz/mystcraft/effects/EffectCrumble.java), [`EffectErosion`](https://github.com/Mystcraft/Mystcraft-Legacy/blob/9bc8ddc061845df0cd5ea47f4fdef773cff786ae/src/main/java/com/xcompwiz/mystcraft/effects/EffectErosion.java)). | #70 implements guarded fluid spread. Erosion's provider is absent from the active Legacy deck; it is deliberately enabled by default in this test slice without adding a saved deck card, per user request. |
@@ -45,15 +45,15 @@ These entry costs are from [`InstabilityData.initialize()`](https://github.com/M
 
 Assets in the supplied local tree: `assets/mystcraft/textures/blocks/decay_{black,blue,green,purple,red,white,yellow}.png`, corresponding decay block/item model JSON, and `assets/mystcraft/sounds/entity/meteor/roar.ogg`. Before importing, review attribution/license and fit modern 16×16 assets. Texture availability does not make an effect active. Use current Minecraft effects/sounds where adaptation is cleaner; no new artwork is needed for this audit.
 
-## Rivencraft boundary and proposed safety contract
+## Rivencraft boundary and current safety contract
 
-[`WritingGrammar`](../src/main/java/net/dnorberg/rivencraft/writing/WritingGrammar.java) classifies `INCOMPLETE` as seeded completion and supported writing defects as accepted instability. `AgeGenerationPlan.compile()` freezes the original writing, repaired active-page indexes, and a provisional writing-instability score before world generation. #64 now persists a versioned score breakdown; saved provider/deck choice remains future work. The plan must not mutate an already-created Age when a data pack changes. Server-side settings may disable execution, but should not rewrite the saved authored score.
+[`WritingGrammar`](../src/main/java/net/dnorberg/rivencraft/writing/WritingGrammar.java) classifies `INCOMPLETE` as seeded completion and supported writing defects as accepted instability. `AgeGenerationPlan.compile()` freezes the original writing, repaired active-page indexes, and a provisional writing-instability score before world generation. #64 persists the versioned score breakdown, and #66 derives and persists the provider/deck choice from that frozen score. The plan must not mutate an already-created Age when a data pack changes. Server-side settings may disable execution, but do not rewrite the saved authored score or provider plan.
 
 For #65, **eligible-to-become-unstable** means a known, supported page whose semantics and resulting world are still deterministic: repeated/conflicting single-choice pages and otherwise valid out-of-order or misplaced pages. The implementation retains every original page, uses the last single-choice page, sorts active categories, and saves 500 per extra/conflicting choice or 100 per misplaced page. These are provisional Rivencraft values, not a full port of every `IAgeSymbol.instabilityModifier`. Missing branches are explicitly classified as zero-cost seeded completion; legal repeated feature/material pages are not automatically errors. **Remain fatal**: missing/duplicate/misordered Link Panel, over-capacity book, unresolved or schema-v1 display-only symbol, unsupported weather/angle/runtime profile/biome/feature, unavailable required optional mod, and any combination the compiler cannot represent safely. Binder and unbound-book previews distinguish blocked writing, seeded completion, and accepted instability before binding; the server revalidates on output. This intentionally differs from Legacy's silent unmatched-symbol skip, universal controller cost assumptions, and modifier-specific dangling costs. A full symbol-specific Legacy penalty port remains a separate balance task, not a claim of parity in this slice.
 
 Automated #65 checks cover classification, preserved input slots on rejection, and an accepted unstable preview. The live output/one-time Age creation check is assigned to in-game testing because the GameTest storage phase stalled when that transaction ran; the test world is not retained.
 
-Issue #66 establishes a server-only scheduler with bounded per-Age actions, provider calls, levels, cooldowns, loaded-chunk candidates, and rotating active-Age admission. World-mutating handlers are **off by default**. No provider effects are registered yet; #67–#70 must enforce protected spawn/link platforms, portals, and provider-specific damage/spread limits before activation. These are **Rivencraft safety adaptations**, not Legacy defaults. Expose score breakdown, selected effects, enablement, and budget suppression in server diagnostics (#72). See [runtime policy](INSTABILITY_RUNTIME.md).
+Issue #66 established a server-only scheduler with bounded per-Age actions, provider calls, levels, cooldowns, loaded-chunk candidates, and rotating active-Age admission. Issues #67–#70 registered the current status, decay, lightning, explosion, meteor, burning, and erosion handlers with protected spawn/link platforms, portal exclusions, and provider-specific damage or spread limits. Instability and world-mutating handlers are enabled by default for newly generated configs to match Legacy's active default; operators can disable them without changing a saved Age. The bounds and protection hooks are **Rivencraft safety adaptations**, not Legacy defaults. Score breakdown, selected effects, enablement, and budget suppression remain part of diagnostics issue #72. See the [runtime policy](INSTABILITY_RUNTIME.md).
 
 M6 owns scoring, selection, effects, controls, and regression. M7 still owns portal/transport and broader polish; M6 must not depend on new M7 structures. An illegal biome/terrain combination that is presently unrepresentable remains a generation failure until a separate, safe compiler path exists; instability must not be used to disguise absent worldgen support. Existing pre-release saves need explicit migration behavior in #73 rather than a silent rescore.