fix(docker): widen chown prune to the entire hermes-agent path

PR #2470 introduces a `:ro` mount for the `hermes-agent-src` named volume
on the WebUI side of `docker-compose.{two,three}-container.yml`. The
WebUI's docker_init.bash unconditionally runs `chown_home_hermeswebui`
which walks `/home/hermeswebui` with `find -exec chown -h {} +`,
pruning only `/home/hermeswebui/.hermes/hermes-agent/.git/objects` (the
narrow #2237 fix for macOS bind mounts).

With the new `:ro` mount, every other file inside the hermes-agent
subtree is also on a read-only filesystem.  `chown` returns `EROFS`,
`find -exec ... +` propagates the non-zero exit, and the wrapping
`chown_home_hermeswebui || error_exit "..."` under `set -e` kills the
container before the WebUI server can run.

Verified locally:

    $ /usr/bin/find /tmp/ftest -exec false {} +
    $ echo $?
    1

So `find` does propagate `-exec` command failures, which the existing
`|| error_exit` then catches.

The WebUI never writes to the agent source — `uv pip install
/home/hermeswebui/.hermes/hermes-agent` is a pure read.  So aligning
ownership inside the agent subtree was always a nicety, not a
requirement.  Widen the prune to skip the entire
`/home/hermeswebui/.hermes/hermes-agent` path.  This also subsumes the
original #2237 case (the `.git/objects` packs are inside the now-pruned
subtree) without needing a separate carve-out.

Test updates:

- Renamed `test_home_chown_skips_hermes_agent_git_objects` →
  `test_home_chown_skips_hermes_agent_subtree`, and pinned the broader
  prune target (`-path ".../hermes-agent" -prune`).
- Added `test_home_chown_helper_documents_readonly_mount_compat` so a
  future maintainer narrowing the prune back to `.git/objects` (and
  re-introducing the EROFS failure mode) trips a regression.

Verified:

- `tests/test_issue2237_docker_chown_git_objects.py` 4/4 pass.
- `tests/test_docker_docs_and_readonly.py` 9/9 pass.
- Full suite: 5738 passed, 0 failed.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

docker_init.bash

@@ -185,8 +185,17 @@ chown_home_hermeswebui() {
   # macOS Docker bind mounts can expose hermes-agent git object packs as
   # read-only host files. The runtime only needs to read those existing objects;
   # requiring chown on them makes startup fail before WebUI can run (#2237).
+  #
+  # Multi-container compose (#2470) additionally mounts the entire
+  # hermes-agent-src volume read-only on the WebUI side because the WebUI only
+  # reads it for `uv pip install`. On a :ro mount, chown returns EROFS for any
+  # file inside the subtree, which would propagate to `set -e` and kill startup
+  # before the WebUI can run. Either way, the WebUI never writes to the agent
+  # source — prune the entire hermes-agent path from the chown walk so a
+  # read-only or partially-read-only mount doesn't break the rest of the home
+  # ownership alignment.
   find /home/hermeswebui \
-    -path "/home/hermeswebui/.hermes/hermes-agent/.git/objects" -prune \
+    -path "/home/hermeswebui/.hermes/hermes-agent" -prune \
     -o -exec chown -h "${WANTED_UID}:${WANTED_GID}" {} +
 }
 

tests/test_issue2237_docker_chown_git_objects.py

@@ -8,13 +8,40 @@ REPO = Path(__file__).resolve().parents[1]
 INIT_SCRIPT = (REPO / "docker_init.bash").read_text(encoding="utf-8")
 
 
-def test_home_chown_skips_hermes_agent_git_objects():
+def test_home_chown_skips_hermes_agent_subtree():
+    """The chown walk must skip the entire hermes-agent mount, not just
+    .git/objects. The original #2237 issue was macOS bind mounts exposing
+    read-only `.git/objects` packs; the post-v0.51.83 multi-container compose
+    setup additionally mounts the whole hermes-agent source tree :ro on the
+    WebUI side (#2470).  Either failure mode breaks the chown walk under
+    `set -e`; pruning the parent path covers both."""
     assert "chown_home_hermeswebui()" in INIT_SCRIPT
-    assert "/home/hermeswebui/.hermes/hermes-agent/.git/objects" in INIT_SCRIPT
-    assert "-prune" in INIT_SCRIPT
+    # The prune target should be the whole hermes-agent subtree, not just
+    # the inner `.git/objects` directory. The old narrower prune was
+    # insufficient once the entire mount became :ro.
+    assert "-path \"/home/hermeswebui/.hermes/hermes-agent\" -prune" in INIT_SCRIPT, (
+        "chown walk must prune the entire hermes-agent path (not just "
+        ".git/objects) so a :ro multi-container mount doesn't EROFS-fail "
+        "the chown."
+    )
     assert 'chown -h "${WANTED_UID}:${WANTED_GID}"' in INIT_SCRIPT
 
 
+def test_home_chown_helper_documents_readonly_mount_compat():
+    """The prune comment must reference the :ro multi-container scenario so
+    future maintainers don't narrow it back to just .git/objects (which would
+    re-introduce the EROFS-on-startup failure for the multi-container setup)."""
+    chown_fn_start = INIT_SCRIPT.index("chown_home_hermeswebui()")
+    chown_fn_end = INIT_SCRIPT.index("\n}\n", chown_fn_start)
+    fn_block = INIT_SCRIPT[chown_fn_start:chown_fn_end]
+
+    assert "read-only" in fn_block.lower() or "ro" in fn_block.lower(), (
+        "chown_home_hermeswebui must document why the entire hermes-agent "
+        "path is pruned (the :ro mount made the previous narrower prune "
+        "insufficient)."
+    )
+
+
 def test_root_init_uses_git_object_safe_chown_helper():
     root_start = INIT_SCRIPT.index('if [ "A${whoami}" == "Aroot" ]; then')
     root_restart = INIT_SCRIPT.index("exec su", root_start)