合并 lane A：清理 AGC 热点三模块不可达实现（272 条 warning）

- 并入本地分支 chore/agc-compile-warnings @ 6d5436541（5 文件）：删除 git_inspect.rs / patchset.rs 全文件、repository_context.rs 收敛到 141 行只保留脱敏链、main.rs 撤 4 行、tests/prompt_source_boundaries.rs 撤 1 条 case。

apps/ai-game-creator-shell/src-tauri/src/main.rs

@@ -105,11 +105,9 @@ pub mod error_report;
 mod game_distribution_publish;
 mod game_package_upload;
 mod game_publish_attempt;
-mod git_inspect;
 mod http_client;
 mod image_inspect;
 mod llm_catalog;
-mod patchset;
 mod platform_asset_upload;
 mod platform_maintenance;
 mod platform_session;
@@ -138,10 +136,8 @@ use command_output::*;
 use command_sandbox::*;
 use commands::*;
 use config::*;
-use git_inspect::*;
 use image_inspect::*;
 use llm_catalog::load_game_creator_llm_models;
-use patchset::*;
 use platform_asset_upload::upload_platform_media_asset;
 use platform_session::*;
 use preview::*;

apps/ai-game-creator-shell/src-tauri/tests/prompt_source_boundaries.rs

@@ -192,10 +192,6 @@ fn prompt_entry_points_load_their_prose_from_external_files() {
             ],
         ),
         ("src/agent/design_tools.rs", &["phase_context"]),
-        (
-            "src/repository_context.rs",
-            &["render_repository_startup_context_for_prompt"],
-        ),
         (
             "src/agent/direct_codex_user_item/wire.rs",
             &["ui_design_code_context_for"],