deps: exclude the broken 3.3.x and refresh the cap comment

Dependabot widened the fastmcp range to <3.5.0 (3.4.2 verified green in CI,
including the pytest-collection path that broke under 3.3.0). Refine the bound
to >=3.0.0,!=3.3.*,<3.5.0 so the known-broken 3.3.0/3.3.1 stay excluded while
3.0-3.2.x support is retained and 3.4.x is allowed, and rewrite the stale
comment that still described the <3.3.0 cap.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: dsarno

pyproject.toml

@@ -30,11 +30,11 @@ classifiers = [
     "Framework :: AsyncIO",
 ]
 dependencies = [
-    # 3.3.0 (released 2026-05-15) ships a circular import in fastmcp.server
-    # that surfaces as "FastMCP server support is not installed" at pytest
-    # collection time on every fresh install. Lift the upper bound once
-    # upstream ships a fix.
-    "fastmcp>=3.0.0,<3.5.0",
+    # fastmcp 3.3.0/3.3.1 ship a circular import in fastmcp.server that surfaces
+    # as "FastMCP server support is not installed" at pytest collection time.
+    # Fixed in 3.4.0 (3.4.2 verified green in CI), so the range allows 3.4.x
+    # again while still excluding the broken 3.3.x.
+    "fastmcp>=3.0.0,!=3.3.*,<3.5.0",
     "websockets>=13.0",
     "pydantic>=2.0",
 ]