feat(watcher): sync SVN working copies automatically

.github/workflows/_test.yml

@@ -81,7 +81,11 @@ jobs:
 
       - name: Install deps (Ubuntu)
         if: startsWith(matrix.os, 'ubuntu')
-        run: sudo apt-get update && sudo apt-get install -y zlib1g-dev
+        run: sudo apt-get update && sudo apt-get install -y subversion zlib1g-dev
+
+      - name: Install deps (macOS)
+        if: startsWith(matrix.os, 'macos')
+        run: brew install subversion
 
       - name: Test
         run: scripts/test.sh CC=${{ matrix.cc }} CXX=${{ matrix.cxx }}
@@ -95,7 +99,7 @@ jobs:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
 
       - name: Install deps (Ubuntu)
-        run: sudo apt-get update && sudo apt-get install -y clang zlib1g-dev
+        run: sudo apt-get update && sudo apt-get install -y clang subversion zlib1g-dev
 
       - name: ThreadSanitizer tests
         run: make -f Makefile.cbm test-tsan CC=clang CXX=clang++
@@ -121,6 +125,7 @@ jobs:
             mingw-w64-clang-${{ matrix.pkg }}-zlib
             make
             git
+            subversion
 
       - name: Test
         shell: msys2 {0}

CONTRIBUTING.md

@@ -60,7 +60,7 @@ src/
     pass_*.c        Individual pipeline passes (definitions, calls, usages, etc.)
     httplink.c      HTTP route extraction (Go/Express/Laravel/Ktor/Python)
   discover/         File discovery with gitignore support
-  watcher/          Git-based background auto-sync
+  watcher/          Git/SVN working-copy background auto-sync
   cli/              CLI subcommands (install, update, uninstall, config)
   ui/               Graph visualization HTTP server (first-party httpd)
 internal/cbm/       Tree-sitter AST extraction (64 languages, vendored C grammars)

Makefile.cbm

@@ -65,7 +65,8 @@ CXXFLAGS_PROD = $(CXXFLAGS_COMMON) -O2
 SANITIZE = -fsanitize=address,undefined -fno-omit-frame-pointer
 EDITOR_TEST_DEFINES = -DCBM_JSON_LIKE_ENABLE_TEST_API=1 \
 	-DCBM_TOML_EDIT_ENABLE_TEST_API=1 -DCBM_YAML_ENABLE_TEST_API=1 \
-	-DCBM_TEXT_EDIT_ENABLE_TEST_API=1 -DCBM_CLI_ENABLE_TEST_API=1
+	-DCBM_TEXT_EDIT_ENABLE_TEST_API=1 -DCBM_CLI_ENABLE_TEST_API=1 \
+	-DCBM_SVN_STATE_ENABLE_TEST_API=1
 CFLAGS_TEST = $(CFLAGS_COMMON) $(EDITOR_TEST_DEFINES) -g -O1 $(SANITIZE)
 CXXFLAGS_TEST = $(CXXFLAGS_COMMON) -g -O1 $(SANITIZE)
 
@@ -236,7 +237,7 @@ UNIXCODER_BLOB_SRC = vendored/nomic/code_vectors_blob.S
 TRACES_SRCS = src/traces/traces.c
 
 # Watcher module (new)
-WATCHER_SRCS = src/watcher/watcher.c
+WATCHER_SRCS = src/watcher/watcher.c src/watcher/svn_state.c
 
 # Git context module (new)
 GIT_SRCS = src/git/git_context.c
@@ -359,7 +360,7 @@ TEST_GRAPH_BUFFER_SRCS = tests/test_graph_buffer.c
 
 TEST_PIPELINE_SRCS = tests/test_registry.c tests/test_pipeline.c tests/test_fqn.c tests/test_route_canon.c tests/test_path_alias.c tests/test_configlink.c tests/test_infrascan.c tests/test_worker_pool.c tests/test_parallel.c tests/test_index_resilience.c
 
-TEST_WATCHER_SRCS = tests/test_watcher.c
+TEST_WATCHER_SRCS = tests/test_watcher.c tests/test_svn_state.c
 
 TEST_LZ4_SRCS = tests/test_lz4.c
 TEST_ZSTD_SRCS = tests/test_zstd.c

README.md

@@ -127,10 +127,12 @@ Enable automatic indexing on MCP session start:
 codebase-memory-mcp config set auto_index true
 ```
 
-When enabled, new projects are indexed automatically on first connection. Previously-indexed projects are registered with the background watcher for ongoing git-based change detection. Configurable file limit: `config set auto_index_limit 50000`.
+When enabled, new projects are indexed automatically on first connection. Previously-indexed projects are registered with the background watcher for ongoing Git or SVN working-copy change detection. Configurable file limit: `config set auto_index_limit 50000`.
 
 Watcher registration is controlled separately by `auto_watch` (default `true`). Set `config set auto_watch false` to keep a session from registering its project with the background watcher — useful when working across many projects and you want each session contained to explicit indexing.
 
+SVN auto-watch requires a trusted system `svn` executable available on `PATH`; project-local clients are not used. Observation runs locally against the working copy and does not query SVN history or add an SVN-specific interval. Git and SVN projects share the watcher's existing adaptive polling cadence and the same indexing pipeline: ordinary changes take the incremental route, while the pipeline may perform a full rebuild when its existing safety threshold requires one. If SVN observation is unavailable or temporarily fails, the current graph remains available and the watcher retries on a later poll.
+
 ### Keeping Up to Date
 
 ```bash
@@ -191,7 +193,7 @@ Removes owned agent config entries, skills, hooks, instructions, and the install
 
 ### Distribution & operation
 - **Single static binary, zero infrastructure**: SQLite-backed, persists to `~/.cache/codebase-memory-mcp/`
-- **Auto-sync**: Background watcher detects file changes and re-indexes automatically
+- **Auto-sync**: Background watcher detects Git and SVN working-copy changes and re-indexes automatically
 - **Route nodes**: REST endpoints are first-class graph entities
 - **CLI mode**: `codebase-memory-mcp cli search_graph '{"project": "my-project", "name_pattern": ".*Handler.*"}'`
 - **Available on**: npm, PyPI, Homebrew, Scoop, Winget, Chocolatey, AUR, `go install`
@@ -598,7 +600,7 @@ See [docs/cbmignore.md](docs/cbmignore.md) for the full `.cbmignore` how-to: syn
 codebase-memory-mcp config list                          # show all settings
 codebase-memory-mcp config set auto_index true           # auto-index on session start
 codebase-memory-mcp config set auto_index_limit 50000    # max files for auto-index
-codebase-memory-mcp config set auto_watch false          # don't register background git watcher (default: true)
+codebase-memory-mcp config set auto_watch false          # don't register background Git/SVN watcher (default: true)
 codebase-memory-mcp config reset auto_index              # reset to default
 ```
 
@@ -712,7 +714,7 @@ src/
   pipeline/           Multi-pass indexing (structure → definitions → calls → HTTP links → config → tests)
   cypher/             Cypher query lexer, parser, planner, executor
   discover/           File discovery (.gitignore, .cbmignore, symlink handling)
-  watcher/            Background auto-sync (git polling, adaptive intervals)
+  watcher/            Background auto-sync (Git/SVN polling, adaptive intervals)
   traces/             Runtime trace ingestion
   ui/                 Embedded HTTP server + 3D graph visualization
   foundation/         Platform abstractions (threads, filesystem, logging, memory)