fix(smolmachines): Linux compat for TSI networking and git-gate paths

Three fixes for Linux smolvm support:

1. Skip force_allowlist DB patch on Linux — patching allowed_cidrs
   into smolvm's state DB crashes TSI boot on Linux. Per-bottle CIDR
   isolation is not enforced on Linux until smolvm fixes the
   --allow-cidr + TSI interaction (known limitation).

2. Patch /etc/git-gate/ references in the staged entrypoint to
   /bot-bottle-data/git-gate/ so git-daemon finds its hooks and
   access-hook at the new consolidated mount path.

3. Drop explicit --net-backend tsi — the default on this smolvm
   build is already TSI; explicitly requesting it is incompatible
   with -p port mappings on Linux.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

bot_bottle/backend/smolmachines/launch.py

@@ -406,15 +406,13 @@ def _stage_sidecar_data(plan: SmolmachinesBottlePlan) -> Path:
         for name in ("entrypoint.sh", "pre-receive", "access-hook"):
             (scripts_dir / name).chmod(0o755)
 
-        # Patch credential paths: the rendered entrypoint hardcodes
-        # /git-gate/creds/; rewrite to the in-VM git-gate subdir.
+        # Patch paths: the rendered entrypoint hardcodes /git-gate/creds/
+        # and /etc/git-gate/ for hooks; rewrite both to the in-VM subdir.
         ep_path = scripts_dir / "entrypoint.sh"
-        ep_path.write_text(
-            ep_path.read_text().replace(
-                "/git-gate/creds/",
-                f"{_GIT_GATE_SCRIPTS_DIR_IN_VM}/creds/",
-            )
-        )
+        text = ep_path.read_text()
+        text = text.replace("/git-gate/creds/", f"{_GIT_GATE_SCRIPTS_DIR_IN_VM}/creds/")
+        text = text.replace("/etc/git-gate/", f"{_GIT_GATE_SCRIPTS_DIR_IN_VM}/")
+        ep_path.write_text(text)
 
         creds_dir = scripts_dir / "creds"
         creds_dir.mkdir(exist_ok=True)