Add runtime proxy actor lookup diagnostics

Introduce Stage 1 runtime lookup diagnostics for the proxy actor base: adds ResolveProxyActorBase and ResolveProxyActorBaseByPluginLocalFormId along with helper checks (IsTestPluginLoaded, IsUsableProxyActorBase, editor/fullname helpers). The code logs plugin load status, editor-ID resolution, and a plugin-local FormID fallback (0x0020A1) while refusing to spawn actors (runtime spawning remains disabled). Adds throttled and one-shot log flags to avoid spam and invokes the diagnostic early on the game-thread before placed-proxy fallback and remote-player selection. Documentation updated (docs/architecture.md and docs/dev-log.md) to record the new diagnostic behavior and next steps.

docs/architecture.md

@@ -34,8 +34,13 @@ both send and receive paths:
     test cell, the game-thread proxy controller moves the single placed proxy to
     a hidden holding position inside `F4TTestCell01` until a valid same-cell
     remote player is available again.
+13. As the first runtime proxy actor manager stage, the same game-thread proxy
+    controller also logs whether `Fallout4Together_Test.esp` is loaded and
+    whether the actor base `F4T_RemotePlayerProxy` resolves by editor ID.
 
-The Fallout 4 plugin still does not dynamically spawn remote actors.
+The Fallout 4 plugin still does not dynamically spawn remote actors. The actor
+base lookup is diagnostic-only and keeps the placed proxy reference as the
+visual representation path.
 
 ## Main Components
 
@@ -54,10 +59,13 @@ The native plugin is responsible for:
   thread
 - Holding that proxy actor at a hidden in-cell position when no valid same-cell
   remote player should be represented
+- Logging staged runtime proxy actor base lookup diagnostics on the same
+  game-thread controller path
 
 Planned later:
 
-- Spawning or moving remote actors
+- Runtime spawning one proxy actor from `F4T_RemotePlayerProxy`
+- Supporting one proxy actor per represented remote `playerId`
 
 ### External Server
 
@@ -108,6 +116,7 @@ Game update logs local movement around 1 Hz
 Networking thread receives packets
 Networking thread stores remote player state
 Game update reads a copied remote player snapshot
+Game update resolves/logs proxy actor base diagnostics
 Game update moves the placed test proxy actor
 ```
 
@@ -118,7 +127,7 @@ update path.
 
 ## Out Of Scope For Current Prototype
 
-- Remote actor spawning
+- Runtime actor spawning
 - Multiple proxy actors
 - Animation graph sync or animation application
 - Combat sync

docs/dev-log.md

@@ -1161,6 +1161,77 @@ snapping without launching multiple Fallout 4 instances.
 
 ---
 
+## 2026-06-02 - Runtime Proxy Actor Manager Stage 1
+
+### Summary
+
+Added lookup-only diagnostics for the future runtime proxy actor path. The
+plugin now confirms whether `Fallout4Together_Test.esp` is loaded and whether
+the actor base `F4T_RemotePlayerProxy` resolves by editor ID or by its confirmed
+plugin-local form ID on the existing game-thread proxy controller path.
+
+### Files Changed
+
+- `plugin/src/F4TProxyActorController.cpp`
+- `docs/dev-log.md`
+- `docs/architecture.md`
+
+### Details
+
+- Added `ResolveProxyActorBase()` as a Stage 1 diagnostic function.
+- Added a test ESP loaded check before actor-base lookup diagnostics.
+- Tightened the diagnostic call site so it runs in `F4TTestCell01` before placed
+  proxy fallback lookup and before remote-player selection.
+- Made runtime proxy actor-base log messages explicit for diagnostic searches:
+  plugin loaded, lookup running, lookup resolved, or lookup failed.
+- Uses `LookupModByName` as a fallback for the ESP loaded check, matching the
+  mod lookup path already used by the placed-reference form ID fallback.
+- Added editor-ID lookup for `F4T_RemotePlayerProxy` as a `RE::TESNPC` actor
+  base and validation that the resolved form still has the expected editor ID.
+- Added confirmed plugin-local FormID fallback lookup:
+  `LookupForm<RE::TESNPC>(0x0020A1, "Fallout4Together_Test.esp")`.
+- Kept the actor-base local ID `0x0020A1` separate from the placed reference
+  local ID `0x0020A2`.
+- Validates the resolved actor base is usable as the future
+  `NEW_REFR_DATA::object` source before reporting success.
+- Accepts the confirmed `LookupForm<RE::TESNPC>` result even if runtime editor
+  ID extraction is unavailable or mismatched; editor ID mismatch is logged as a
+  warning instead of rejecting the actor base.
+- Logs fallback diagnostics including runtime form ID, local form ID, form type,
+  `TESNPC` status, editor ID if available, display name if available, and
+  whether the form was accepted.
+- Logs whether actor-base lookup succeeded through editor ID lookup or
+  plugin-local FormID fallback.
+- Added clear one-shot or throttled logs for test ESP load status, actor-base
+  lookup success, missing editor ID, or wrong form type.
+- Did not call `CreateReferenceAtLocation` and did not spawn runtime actors.
+- Left placed proxy lookup, smoothing, special movement snapping, holding
+  lifecycle, and sneak-state observation unchanged.
+- Left networking protocol, Python server code, and fake-client tooling
+  unchanged.
+
+### Testing
+
+- Ran `xmake build` from `plugin`; it succeeded.
+- Pending: launch Fallout 4 through F4SE, load `Fallout4Together_Test.esp`, and
+  `coc F4TTestCell01`.
+- Pending: confirm `Fallout4Together.log` reports the test ESP load status and
+  `F4T_RemotePlayerProxy` lookup result.
+- Pending: confirm the existing placed proxy fallback still represents one fake
+  client and still holds/restores correctly.
+
+### Known Issues
+
+- Runtime actor spawning is intentionally not implemented in this stage.
+
+### Next Steps
+
+- Run the build and in-game lookup diagnostics.
+- After lookup is proven stable, proceed to Stage 2: one game-thread-only runtime
+  spawn diagnostic in `F4TTestCell01` while keeping the placed reference fallback.
+
+---
+
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