fix(pilot): strip opencode $schema + defensive harvest dict-strip

- opencode_review.install_config: opencode 1.3.10 rejects factory
  opencode.json$'\''s top-level "$schema" key with 'Unrecognized key'
  at parse time, causing every fresh review to fail as the misleading
  'opencode empty text (rc=0)'. Add a small drop-list of known-bad
  top-level keys + a sanitizer applied to both the fast (no-env) and
  slow (env-substituted) write paths.

- feedback_harvest: Gitea versions occasionally serialize reaction
  content / inline-comment resolver as a dict instead of a string,
  crashing harvester with 'dict object has no attribute strip'. Coerce
  both via str() with a brief comment documenting the WHY.

Affected reviews: techspark/suaspark-dashboard #11 (fixed),
PRAgent reviews on PR #9 era (recovered).
Verified: opencode 1.3.10 emits real '### Summary of Changes' body.

pilot/opencode_review.py

@@ -421,9 +421,33 @@ def install_config(src: str, dst: str) -> bool:
         return False
     default_url = os.environ.get("PRAGENT_MODEL_BASE_URL", "").strip()
     default_key = os.environ.get("PRAGENT_MODEL_API_KEY", "").strip()
+
+    # Strip keys opencode's runtime rejects on every version bump we touch. The
+    # factory `opencode.json` is committed for documentation (so `$schema`
+    # stays in the file for editor IntelliSense), but opencode 1.3.10 errors
+    # with "Unrecognized key: schema" at config-parse time and refuses to
+    # register ANY provider/model — surfacing to the user as the misleading
+    # "opencode empty text (rc=0)" failure post. Keep the drop list small and
+    # documented; smoke-test before adding more.
+    _OPENCODE_INCOMPATIBLE_TOP_KEYS = ("$schema",)
+
+    def _sanitize_and_write(cfg: dict) -> None:
+        for k in _OPENCODE_INCOMPATIBLE_TOP_KEYS:
+            cfg.pop(k, None)
+        with open(dst, "w", encoding="utf-8") as f:
+            json.dump(cfg, f, indent=2)
+
     if not default_url and not default_key:
-        # Fast path: no env at all → commit copy is fine, no rewrite needed.
-        shutil.copy2(src, dst)
+        # Fast path: no env at all → still sanitize (the schema key would
+        # poison every fresh-pod warm-up if we skipped).
+        try:
+            with open(src, encoding="utf-8") as f:
+                cfg = json.load(f)
+            _sanitize_and_write(cfg)
+        except (OSError, ValueError):
+            # If we can't parse, fall back to verbatim copy — opencode will
+            # report the parse error itself, no need to hide it.
+            shutil.copy2(src, dst)
         return True
     try:
         with open(src, encoding="utf-8") as f:
@@ -439,8 +463,7 @@ def install_config(src: str, dst: str) -> bool:
                 prov["options"]["baseURL"] = url
             if key:
                 prov["options"]["apiKey"] = key
-        with open(dst, "w", encoding="utf-8") as f:
-            json.dump(cfg, f, indent=2)
+        _sanitize_and_write(cfg)
     except (OSError, ValueError, AttributeError):
         # A malformed config is opencode's problem to report, not ours to hide.
         shutil.copy2(src, dst)