Extract bos-settings to its own repo; add breadhelp; JSON-driven Hyprland config

bos-settings moves to git.breadway.dev/Breadway/bos-settings (full history
preserved via git-filter-repo) so its release cadence is decoupled from
BOS's own. breadhelp takes its place as this repo's workspace member: a
GTK4 onboarding/help center replacing the old bos-welcome/bos-keybinds
bash scripts with searchable guides, an interactive keybind viewer
(sourced from the new keybinds.toml, not parsed out of hyprland.lua or
hardcoded), a troubleshooting wizard with one-click fixes, and a proper
first-run tour. bos-netcheck extracts bos-welcome's network-check half,
which still needs to run every login independent of breadhelp's own
first-run gating.

hyprland.lua's keybinds/settings/monitors/autostart are now JSON-driven
(binds.json/settings.json/monitors.json/autostart.json) with every
loader pcall-wrapped and falling back to hardcoded defaults per field on
bad or missing config, so bread* apps (bos-settings' new editors, and
breadhelp's keybind viewer) can read/write this config without ever
being able to leave the compositor unable to start.

CI's package.yml now builds breadhelp instead of bos-settings on tag
push; bos-settings needs its own equivalent workflow in its new repo
(not yet set up).

breadhelp/content/README.md

@@ -0,0 +1,28 @@
+# breadhelp content
+
+Guides and troubleshooting data, installed to `/usr/share/breadhelp/content/`.
+User overrides/additions live at `~/.local/share/breadhelp/content/` (same
+shape; a colliding guide directory name wins wholesale over the system copy).
+
+Categories are just top-level directories here — the Learn tab lists whatever
+exists, so adding a category is a content change, not a code change:
+
+```
+getting-started/
+daily-use/
+customization/
+apps/
+troubleshooting/
+  _symptoms/          # troubleshooting wizard's symptom-tree *.toml files
+advanced/
+```
+
+Each guide is a directory with:
+
+- `meta.toml` — title, difficulty, tags, related guides, estimated time
+- `content.md` — the guide body (constrained Markdown subset + `[Run]`/
+  `[Show Keybind]` tags — see `src/content/markdown.rs`)
+- `content.beginner.md` — optional, used in Beginner/Dad mode instead of
+  `content.md` when present
+
+Content lands starting at M2.