feat(codex): set gpt-5.4 defaults for plan mode and long context

- switch managed codex config model to gpt-5.4

- set plan_mode_reasoning_effort to xhigh

- set model_context_window/model_auto_compact_token_limit defaults

- add auth-sync tests for create/rewrite behavior

Closes #109

Closes #111

Author: skulidropek

packages/lib/src/core/templates-entrypoint/codex.ts

@@ -64,8 +64,11 @@ else
     mkdir -p "$(dirname "$CODEX_CONFIG_FILE")" || true
     cat <<'EOF' > "$CODEX_CONFIG_FILE"
 # docker-git codex config
-model = "gpt-5.3-codex"
+model = "gpt-5.4"
+model_context_window = 1050000
+model_auto_compact_token_limit = 945000
 model_reasoning_effort = "xhigh"
+plan_mode_reasoning_effort = "xhigh"
 personality = "pragmatic"
 
 approval_policy = "never"

packages/lib/src/usecases/auth-sync-helpers.ts

@@ -28,20 +28,23 @@ const JsonRecordFromStringSchema = Schema.parseJson(JsonRecordSchema)
 const defaultEnvContents = "# docker-git env\n# KEY=value\n"
 const codexConfigMarker = "# docker-git codex config"
 
-// CHANGE: enable web search tool in default Codex config (top-level)
-// WHY: avoid deprecated legacy flags and keep config minimal
-// QUOTE(ТЗ): "да убери легаси"
-// REF: user-request-2026-02-05-remove-legacy-web-search
+// CHANGE: switch default model to gpt-5.4 and pin xhigh reasoning for default + plan mode
+// WHY: keep plan mode aligned with development mode while preserving long-context defaults
+// QUOTE(ТЗ): "Сделать plan mode тоже с xhigh режимом как и разработка по дефолту. Так же заменить модель на gpt-5.4"
+// REF: github-issue-109
 // SOURCE: n/a
-// FORMAT THEOREM: ∀c: config(c) -> web_search(c)="live"
+// FORMAT THEOREM: ∀c: config(c) -> model(c)="gpt-5.4" ∧ reasoning(c)=xhigh ∧ plan_reasoning(c)=xhigh
 // PURITY: CORE
 // EFFECT: n/a
 // INVARIANT: default config stays deterministic
 // COMPLEXITY: O(1)
 export const defaultCodexConfig = [
   "# docker-git codex config",
-  "model = \"gpt-5.3-codex\"",
+  "model = \"gpt-5.4\"",
+  "model_context_window = 1050000",
+  "model_auto_compact_token_limit = 945000",
   "model_reasoning_effort = \"xhigh\"",
+  "plan_mode_reasoning_effort = \"xhigh\"",
   "personality = \"pragmatic\"",
   "",
   "approval_policy = \"never\"",

packages/lib/tests/usecases/auth-sync.test.ts

@@ -73,6 +73,63 @@ describe("syncGithubAuthKeys", () => {
     expect(next).toBe(target)
   })
 
+  it.effect("creates codex config with gpt-5.4 and long-context overrides", () =>
+    withTempDir((root) =>
+      Effect.gen(function*(_) {
+        const fs = yield* _(FileSystem.FileSystem)
+        const path = yield* _(Path.Path)
+        const codexDir = path.join(root, ".orch", "auth", "codex")
+        const configPath = path.join(codexDir, "config.toml")
+
+        yield* _(ensureCodexConfigFile(root, ".orch/auth/codex"))
+
+        const configText = yield* _(fs.readFileString(configPath))
+        expect(configText).toContain("model = \"gpt-5.4\"")
+        expect(configText).toContain("model_context_window = 1050000")
+        expect(configText).toContain("model_auto_compact_token_limit = 945000")
+        expect(configText).toContain("model_reasoning_effort = \"xhigh\"")
+        expect(configText).toContain("plan_mode_reasoning_effort = \"xhigh\"")
+      })
+    ).pipe(Effect.provide(NodeContext.layer)))
+
+  it.effect("rewrites managed codex config to include gpt-5.4 and plan mode xhigh", () =>
+    withTempDir((root) =>
+      Effect.gen(function*(_) {
+        const fs = yield* _(FileSystem.FileSystem)
+        const path = yield* _(Path.Path)
+        const codexDir = path.join(root, ".orch", "auth", "codex")
+        const configPath = path.join(codexDir, "config.toml")
+        const legacyManagedConfig = [
+          "# docker-git codex config",
+          "model = \"gpt-5.3-codex\"",
+          "model_reasoning_effort = \"xhigh\"",
+          "personality = \"pragmatic\"",
+          "",
+          "approval_policy = \"never\"",
+          "sandbox_mode = \"danger-full-access\"",
+          "web_search = \"live\"",
+          "",
+          "[features]",
+          "shell_snapshot = true",
+          "multi_agent = true",
+          "apps = true",
+          "shell_tool = true",
+          ""
+        ].join("\n")
+
+        yield* _(fs.makeDirectory(codexDir, { recursive: true }))
+        yield* _(fs.writeFileString(configPath, legacyManagedConfig))
+        yield* _(ensureCodexConfigFile(root, ".orch/auth/codex"))
+
+        const next = yield* _(fs.readFileString(configPath))
+        expect(next).toContain("model = \"gpt-5.4\"")
+        expect(next).toContain("model_context_window = 1050000")
+        expect(next).toContain("model_auto_compact_token_limit = 945000")
+        expect(next).toContain("model_reasoning_effort = \"xhigh\"")
+        expect(next).toContain("plan_mode_reasoning_effort = \"xhigh\"")
+      })
+    ).pipe(Effect.provide(NodeContext.layer)))
+
   it.effect("ignores permission-denied codex config rewrites", () =>
     withTempDir((root) =>
       Effect.gen(function*(_) {