feat(hub): split the group UI into a pluggable "applications" architecture

GroupPage's 6620-line app.js carried Chat and Files wedged in directly, with
no way to add another group-level app without touching the shell itself. It
is now app.js (routing, non-group pages) plus nine focused files — apps.js
(the registry), chat-app.js, files-app.js, video-player.js, group-page.js
(the shell), group-settings.js, hub-client.js, icon.js and file-utils.js —
with docs/apps.md as the checklist for adding one (Videos/Music/Photos are
sketched there, not built).

Node side gained the matching enablement mechanism, mirroring
member_upload exactly: a roster setting, a signed apps_enabled op enforced
by _has_admin_authority, exposed in the handshake ack. Operators toggle
applications per group from Settings, which also gained a small reorder:
Invite, Pairing, Applications, Shared directories, Uploads, danger zone,
Your devices, Members.

Two bugs surfaced during the split, both missing an import across the new
file boundary and invisible to node --check or a module-load probe since
they only throw when the code path actually runs:

- group-page.js called onRefreshAuth on a stale-token handshake rejection,
  but app.js never imported refreshAccessToken from hub-client.js — so a
  brand new member (including a group's own creator) hit "Not a member of
  this group" and the retry silently failed, throwing before it could
  refresh the token.
- chat-app.js called getLocale() for message timestamps without importing
  it from i18n.js. Opening Chat on a group with real messages threw mid-
  render; uncaught, that appears to wedge Preact's render scheduler, so
  every button on the page stopped responding until reload.

Caught the second class of bug with a proper no-undef audit across all
split files (a temporarily installed ESLint 9, since the system one is too
old to parse this codebase's syntax) rather than trusting grep. 827 tests
pass; 6 new ones cover the apps_enabled policy.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016SF6RKNBKg9qejmoMJ9ybA

1 files changed, 17 insertions, 5 deletions

diff --git a/packages/meshbay-hub/tests/test_spa_ordering.py b/packages/meshbay-hub/tests/test_spa_ordering.py
index dfc92f9..d00b9a0 100644
--- a/packages/meshbay-hub/tests/test_spa_ordering.py
+++ b/packages/meshbay-hub/tests/test_spa_ordering.py
@@ -113,14 +113,26 @@ def test_the_ack_still_verifies_the_announced_node_key():
 # Users tab referencing `doInvite`, `members` and `adminId` — none of which are
 # defined there.
 
+# The group-page refactor split what used to be one app.js into one file per
+# "application" (chat-app.js, files-app.js, video-player.js) plus
+# group-settings.js and the group shell itself, group-page.js. AdminPage and
+# App() stayed in app.js. `_component` below is told which file to read a
+# given top-level component from.
 APP = STATIC / "app.js"
+COMPONENT_FILES = {
+    "GroupSettingsPanel": STATIC / "group-settings.js",
+    "GroupPage": STATIC / "group-page.js",
+    "ChatPanel": STATIC / "chat-app.js",
+    "FilesPanel": STATIC / "files-app.js",
+    "VideoPlayer": STATIC / "video-player.js",
+}
 
 
 def _component(name: str) -> str:
     """The source of one top-level `function Name(...)`, up to the next one."""
-    source = APP.read_text()
+    source = COMPONENT_FILES.get(name, APP).read_text()
     start = source.find(f"\nfunction {name}(")
-    assert start != -1, f"{name} is gone from app.js — update this test"
+    assert start != -1, f"{name} is gone — update this test"
     end = source.find("\nfunction ", start + 1)
     return source[start:end if end != -1 else len(source)]
 
@@ -220,7 +232,7 @@ def test_no_caller_waits_for_one_chunk_at_a_time():
 # two ends of that, since neither shows up in any Python test.
 
 def test_leaving_a_group_hands_the_transport_over_rather_than_closing_it():
-    app = APP.read_text()
+    app = _component("GroupPage")
     cleanup = app[app.index("    return () => {\n      cancelled = true;"):]
     cleanup = cleanup[:cleanup.index("\n  }, [groupId")]
     assert "releaseWhenIdle" in cleanup, (
@@ -252,7 +264,7 @@ def test_a_multi_file_download_waits_for_each_picker():
     meant the first opened a dialog and the rest were rejected — two files
     selected, one file downloaded.
     """
-    app = APP.read_text()
+    app = STATIC.joinpath("files-app.js").read_text()
     # Anchored on the loop rather than on the markup around it: the toolbar
     # moved from a dropdown to icon buttons and took the old wrapper with it,
     # while the property under test — one picker at a time — did not change.
@@ -269,7 +281,7 @@ def test_links_in_chat_are_built_as_elements_not_markup():
     never HTML, and only for http(s) — otherwise javascript: would be one
     message away from running here.
     """
-    app = APP.read_text()
+    app = STATIC.joinpath("chat-app.js").read_text()
     fn = app[app.index("function linkify("):]
     fn = fn[:fn.index("\nfunction ", 1)]
     assert "innerHTML" not in fn and "dangerouslySetInnerHTML" not in fn