compat(plugins): temporary import-path shims for external plugins — ONE commit, revert on schedule

The Sep 2026 decomposition (PR #102117) makes internal import paths a non-API: names now live in
the focused modules that define them. This commit is the ONLY thing keeping the old paths alive,
so external plugins have time to update. It is deliberately a single, unsquashed commit:

    git revert <this sha>

removes every shim, stub and manifest at once on the announced date. Nothing in-tree may depend on
these pointers: scripts/check_compat_pointers.py (wired into lint.yml) fails CI if it does.

What it adds (see COMPAT_MANIFEST.md, compat_manifest.json):
- 332 facade modules get one delimited `PLUGIN-COMPAT` block appended at the end of the file
- 1,172 moved names resolved lazily via a module `__getattr__` (PEP 562) — never a top-level import,
  so no import cycles; facades that already had `__getattr__` get a chained one
- 592 third-party/stdlib names the old modules used to expose, with their original import statements
- 266 public definitions that had been deleted as unused, restored byte-for-byte from the pre-decomposition
  tree (+40 private helpers and 16 imports pulled in only because a restored definition needs them)
- 3 deleted modules recreated as re-export stubs (gateway/startup_watchdog, hermes_cli/observability/
  relay_runtime, tools/environments/modal_utils)
- private names (`_x`) get no pointer: they were never API (3,792 skipped)

Verified: all 335 touched modules import under a fresh HERMES_HOME and every manifest name resolves;
the lint reports zero in-tree uses; ruff clean; targeted suites unchanged.

cli.py

@@ -4574,3 +4574,69 @@ if __name__ == "__main__":
     import fire
 
     fire.Fire(main)
+
+
+# ---- BEGIN PLUGIN-COMPAT (revert-scheduled; see COMPAT_MANIFEST.md) ----
+# Names external plugins imported from this module before the Sep 2026 decomposition.
+# Internal code MUST NOT use these (scripts/check_compat_pointers.py fails CI if it does).
+# The whole block is removed by reverting the commit that added it.
+from prompt_toolkit.layout.menus import CompletionsMenu  # noqa: F401,E402
+from prompt_toolkit.filters import Condition  # noqa: F401,E402
+from prompt_toolkit.layout import ConditionalContainer  # noqa: F401,E402
+from prompt_toolkit.layout.processors import ConditionalProcessor  # noqa: F401,E402
+from prompt_toolkit.layout.dimension import Dimension  # noqa: F401,E402
+from prompt_toolkit.history import FileHistory  # noqa: F401,E402
+from prompt_toolkit.layout import FormattedTextControl  # noqa: F401,E402
+from prompt_toolkit.layout import HSplit  # noqa: F401,E402
+from prompt_toolkit.key_binding import KeyBindings  # noqa: F401,E402
+from prompt_toolkit.layout import Layout  # noqa: F401,E402
+from prompt_toolkit.styles import Style as PTStyle  # noqa: F401,E402
+from rich.panel import Panel  # noqa: F401,E402
+from prompt_toolkit.layout.processors import PasswordProcessor  # noqa: F401,E402
+from prompt_toolkit.layout.processors import Processor  # noqa: F401,E402
+from prompt_toolkit.widgets import TextArea  # noqa: F401,E402
+from prompt_toolkit.layout.processors import Transformation  # noqa: F401,E402
+from prompt_toolkit.layout import Window  # noqa: F401,E402
+from prompt_toolkit.layout import WindowAlign  # noqa: F401,E402
+import base64  # noqa: F401,E402
+import concurrent.futures  # noqa: F401,E402
+import copy  # noqa: F401,E402
+from rich import box as rich_box  # noqa: F401,E402
+import tempfile  # noqa: F401,E402
+
+
+_PLUGIN_COMPAT_LAZY = {
+    'AIAgent': ('run_agent', 'AIAgent'),
+    'CanonicalUsage': ('agent.usage_pricing', 'CanonicalUsage'),
+    'DEFAULT_BROWSER_CDP_URL': ('hermes_cli.browser_connect', 'DEFAULT_BROWSER_CDP_URL'),
+    'HERMES_AGENT_LOGO': ('hermes_cli.banner', 'HERMES_AGENT_LOGO'),
+    'HERMES_CADUCEUS': ('hermes_cli.banner', 'HERMES_CADUCEUS'),
+    'SlashCommandAutoSuggest': ('hermes_cli.commands_completion', 'SlashCommandAutoSuggest'),
+    'SlashCommandCompleter': ('hermes_cli.commands_completion', 'SlashCommandCompleter'),
+    'build_welcome_banner': ('hermes_cli.banner', 'build_welcome_banner'),
+    'display_hermes_home': ('hermes_constants', 'display_hermes_home'),
+    'estimate_usage_cost': ('agent.usage_pricing', 'estimate_usage_cost'),
+    'get_all_toolsets': ('toolsets', 'get_all_toolsets'),
+    'get_job': ('cron.jobs', 'get_job'),
+    'get_toolset_for_tool': ('model_tools', 'get_toolset_for_tool'),
+    'get_toolset_info': ('toolsets', 'get_toolset_info'),
+    'init_skin_from_config': ('hermes_cli.skin_engine', 'init_skin_from_config'),
+    'is_browser_debug_ready': ('hermes_cli.browser_connect', 'is_browser_debug_ready'),
+    'is_table_divider': ('agent.markdown_tables', 'is_table_divider'),
+    'looks_like_table_row': ('agent.markdown_tables', 'looks_like_table_row'),
+    'manual_chrome_debug_command': ('hermes_cli.browser_connect', 'manual_chrome_debug_command'),
+    'print_config_warnings': ('hermes_cli.config', 'print_config_warnings'),
+    'prompt_for_secret': ('hermes_cli.callbacks', 'prompt_for_secret'),
+    'set_friendly_tool_labels': ('agent.display', 'set_friendly_tool_labels'),
+    'set_tool_preview_max_len': ('agent.display', 'set_tool_preview_max_len'),
+    'setup_logging': ('hermes_logging', 'setup_logging'),
+}
+
+
+def __getattr__(name):  # PEP 562 — lazy so no import cycles
+    target = _PLUGIN_COMPAT_LAZY.get(name)
+    if target is None:
+        raise AttributeError(f"module {__name__!r} has no attribute {name!r}")
+    import importlib
+    return getattr(importlib.import_module(target[0]), target[1])
+# ---- END PLUGIN-COMPAT ----