feat(protocol2): house registry board (Part B ph.3)

Overlay BridgeHousing (new): a diff sweep over BaseHouse.AllHouses ->
house.update / house.remove (owner, region, location, decay level, co-owners,
friends, placement price), complementing the existing house.decay transition
feed. HousingSweepSeconds (300s); wired into [bridge reload|sweepnow|status.
Stock ServUO has no "for sale" flag, so this is an owner->houses registry;
price is the placement value, not a listing.

Sidecar: houses board table with upsert/delete/all; main routes house.update/
remove into it; GET /houses served from the store.

Docs: INTEGRATION.md house.* events + /houses endpoint; PROTOCOL_2 ph.3 built.

Verified: sidecar cargo check clean; overlay compiles in the full ServUO
Scripts tree (0 errors, 0 warnings). Live run pending.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

link/INTEGRATION.md

@@ -296,6 +296,25 @@ Who's online and where. A population snapshot is polled (`PresenceSweepSeconds`,
  "who":{"serial":"0x1A2B","name":"Darrow","acct":"whitlocktech","player":true},"t":...}
 ```
 
+#### Houses (Protocol 2.0)
+
+The house registry — one row per house, complementing the `house.decay` *transition* feed (§ above). Polled (`HousingSweepSeconds`, default 300s) and diffed like the other boards.
+
+| kind | fields | notes |
+|------|--------|-------|
+| `house.update` | `serial`, `name`, `owner` (actor or null), `coOwners`, `friends`, `region`, `map`, `x`,`y`,`z`, `decay`, `price`, `builtOn`, `lastRefreshed` | A house's owner/region/decay/co-owners changed, or first sight this connection. `decay` is the level name (e.g. `LikeNew`). `price` is the placement value — **stock ServUO has no "for sale" flag**, so this is not a listing. |
+| `house.remove` | `serial` | The house was demolished or no longer exists. Drop the row. |
+
+```json
+{"kind":"house.update","serial":"0x40001234","name":"The Silver Anvil","decay":"LikeNew",
+ "price":432100,"map":"Felucca","x":1420,"y":1631,"z":0,"region":"Britain",
+ "owner":{"serial":"0x1A2B","name":"Darrow","acct":"whitlocktech","player":true},
+ "coOwners":2,"friends":5,"builtOn":"2026-01-02T00:00:00Z","lastRefreshed":"2026-07-10T00:00:00Z",
+ "t":1752489280000}
+```
+
+Render from `GET /houses` (§6) on connect, then keep live with these events.
+
 ---
 
 ## 5. REST — read queries
@@ -602,6 +621,18 @@ GET /online
 
 The current online population — total plus per-facet and per-region breakdowns. The latest `presence.online` snapshot (from SQLite, so it survives a sidecar restart); keep it live with the `presence.online` stream (§4). `count: 0` with empty maps if the shard hasn't reported yet. For the population time series, `GET /history?kind=presence.online`.
 
+### House registry (Protocol 2.0)
+
+```
+GET /houses
+→ { "houses": [ {"kind":"house.update","serial":"0x40001234","name":"The Silver Anvil",
+      "decay":"LikeNew","price":432100,"map":"Felucca","x":1420,"y":1631,"z":0,"region":"Britain",
+      "owner":{"serial":"0x1A2B","name":"Darrow","acct":"whitlocktech","player":true},
+      "coOwners":2,"friends":5,"builtOn":"...","lastRefreshed":"...","t":...}, ... ] }
+```
+
+Every house's latest snapshot — owner→houses map. Served from the sidecar's projection, kept current by the `house.*` stream (§4). Ordered by name. Survives a sidecar restart.
+
 ---
 
 ## 7. Status codes

link/PROTOCOL_2.md

@@ -382,7 +382,7 @@ If the website mirrors rosters/links (it does — `store.record_link`), it must
 
 1. ~~**Guilds + governors.**~~ **Built (2026-07-17), compiles clean both sides.** `BridgeSocial.cs` (guild sweep + `JoinGuild` → `guild.update`/`guild.remove`/`guild.join`) and `BridgeGovernance.cs` (city sweep → `city.update`, gated on `CityLoyaltySystem.Enabled`), `GuildSweepSeconds` (60s) / `CitySweepSeconds` (300s) config, both wired into `[bridge reload|sweepnow|status`. Sidecar `guilds`/`governors` board tables + `GET /guilds`, `/governors` served from the store (the §12.2 snapshot rule). Shared `BridgeJson.Actor` writer (serial/name/acct/webId/player). **Deviation from the §10 sketch:** the wire uses full-state `guild.update`/`city.update` upserts (website derives "created"/"governor changed" from the board) rather than discrete `guild.created`/`city.governor` events — this avoids a reconnect re-emit looking like a storm of creations, matching the proven `champ.update` model. *Live end-to-end run still pending.*
 2. ~~**Presence.**~~ **Built (2026-07-17), compiles clean both sides.** `BridgePresence.cs`: a `presence.online` sweep (total + per-facet + per-region, emitted on change) and real-time `region.enter` (`EventSink.OnEnterRegion`, player-filtered). `PresenceSweepSeconds` (30s), wired into `[bridge`. `GET /online` serves the latest snapshot from the event store (population series via `/history?kind=presence.online`). *Live run pending.*
-3. **Housing registry.** Extend the decay sweep to a full owner→houses list → `GET /houses`. (Selected from the §11 menu. Note: stock ServUO has no "for sale" flag on houses, so the registry is owner→houses; for-sale is dropped.)
+3. ~~**Housing registry.**~~ **Built (2026-07-17), compiles clean both sides.** `BridgeHousing.cs`: a house sweep over `BaseHouse.AllHouses` → `house.update`/`house.remove` (owner, region, location, decay, co-owners, friends, price), complementing the existing `house.decay` transition feed. `HousingSweepSeconds` (300s), wired into `[bridge`. Sidecar `houses` board + `GET /houses`. (Stock ServUO has no "for sale" flag, so this is owner→houses; `price` is the placement value, not a listing.) *Live run pending.*
 4. **Titles.** `char.profile` `titles` block (§10.3) — no new stream, folds into `BridgeProfile`.
 5. **Factions/VvV** — only after confirming which system the shard runs; stream just the enabled one.