fix: exclude matrix from [all] extras — python-olm is upstream-broken (#4615)

python-olm (required by matrix-nio[e2e]) fails to build on modern macOS:
- CMake 4 rejects vendored libolm's cmake_minimum_required(VERSION 3.4)
- Apple Clang 21+ rejects a C++ type error in include/olm/list.hh
- Upstream libolm repo is archived, no fix forthcoming

Including matrix in [all] causes the entire extras install to fail during
`hermes update`, silently dropping all other extras (telegram, discord,
slack, cron, etc.) when the fallback kicks in.

The [matrix] extra is preserved for opt-in install:
  pip install 'hermes-agent[matrix]'

Closes #4178

pyproject.toml

@@ -76,7 +76,10 @@ all = [
   "hermes-agent[modal]",
   "hermes-agent[daytona]",
   "hermes-agent[messaging]",
-  "hermes-agent[matrix]",
+  # matrix excluded: python-olm (required by matrix-nio[e2e]) is upstream-broken
+  # on modern macOS (archived libolm, C++ errors with Clang 21+). Including it
+  # here causes the entire [all] install to fail, dropping all other extras.
+  # Users who need Matrix can install manually: pip install 'hermes-agent[matrix]'
   "hermes-agent[cron]",
   "hermes-agent[cli]",
   "hermes-agent[dev]",

tests/test_project_metadata.py

@@ -11,8 +11,12 @@ def _load_optional_dependencies():
     return project["optional-dependencies"]
 
 
-def test_all_extra_includes_matrix_dependency():
+def test_matrix_extra_exists_but_excluded_from_all():
+    """matrix-nio[e2e] depends on python-olm which is upstream-broken on modern
+    macOS (archived libolm, C++ errors with Clang 21+).  The [matrix] extra is
+    kept for opt-in install but deliberately excluded from [all] so one broken
+    upstream dep doesn't nuke every other extra during ``hermes update``."""
     optional_dependencies = _load_optional_dependencies()
 
     assert "matrix" in optional_dependencies
-    assert "hermes-agent[matrix]" in optional_dependencies["all"]
+    assert "hermes-agent[matrix]" not in optional_dependencies["all"]