Align install-dispatch version check with the gate predicate (F2)

The _can_self_update() gate is major-aware (major>4 or (major==4 and
minor>=4)), but _install_zip / _install_zip_inline still keyed off
`minor >= 4` only. On a future Godot 5.0 (major=5, minor=0) the gate
would let the user in expecting the seamless runner reload, but the
minor-only check would route them to the pre-4.4 inline extract +
"Restart editor" path — the crash-prone flow the gate exists to avoid.

Route both install-dispatch checks through the same
_version_can_self_update(major, minor) predicate (already unit-tested
for 4.3/4.4/4.6/5.0) so the gate and the dispatch can't disagree.
No behavior change on 4.4-4.6; fixes the latent 5.x inconsistency.

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

Author: dsarno

plugin/addons/godot_ai/utils/update_manager.gd

@@ -340,7 +340,11 @@ func _install_zip() -> void:
 		_plugin != null
 		and _plugin.has_method("install_downloaded_update")
 	)
-	if int(version.get("minor", 0)) >= 4 and has_runner:
+	## Same major-aware predicate as the _can_self_update() gate, so a future
+	## Godot 5.x (minor 0) takes the runner path the gate promised — not the
+	## pre-4.4 inline extract. A bare `minor >= 4` here would route 5.0 to the
+	## crash-prone inline path even though the gate let it in.
+	if _version_can_self_update(int(version.get("major", 0)), int(version.get("minor", 0))) and has_runner:
 		install_state_changed.emit({"button_text": "Reloading..."})
 		## Runner takes over: plugin tears down, runner extracts + scans +
 		## re-enables. `install_downloaded_update` calls
@@ -393,7 +397,7 @@ func _install_zip_inline(version: Dictionary) -> void:
 	if _plugin != null and _plugin.has_method("prepare_for_update_reload"):
 		_plugin.prepare_for_update_reload()
 
-	if int(version.get("minor", 0)) >= 4:
+	if _version_can_self_update(int(version.get("major", 0)), int(version.get("minor", 0))):
 		install_state_changed.emit({"button_text": "Scanning..."})
 		## Filesystem scan must complete before plugin reload — otherwise
 		## plugin.gd re-parses against a ClassDB that hasn't seen the new