chore(orbit): help modal with 9-section walk-through

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

src/locales/en.ts

@@ -1505,6 +1505,30 @@ export const enTranslation = {
     hostOnline: 'Host online',
     endTooltip: 'End session',
     leaveTooltip: 'Leave session',
+    helpTooltip: 'How Orbit works',
+    helpTitle: 'How Orbit works',
+    helpIntro: 'Orbit turns Psysonic into a shared listening room. A host picks the music; guests listen in sync and can suggest tracks.',
+    helpHostOnly: '(host)',
+    helpSec1Title: 'What is Orbit?',
+    helpSec1Body: "A \"listen together\" mode — the host drives playback, guests tune in. Everything runs through playlists on your own Navidrome server; no external infrastructure.",
+    helpSec2Title: 'Host and guests',
+    helpSec2Body: 'Host controls playback (play / pause / skip / seek) and decides when the session ends. Guests follow the host\'s playback, can suggest tracks, and leave or re-join any time. Only the host can kick or permanently ban a participant.',
+    helpSec2WarnHead: 'Important: separate accounts.',
+    helpSec2WarnBody: "Every participant needs their own Navidrome account. If host and guest sign in with the same user their submissions collide and the host never sees the guest's suggestions.",
+    helpSec3Title: 'Starting and inviting',
+    helpSec3Body: 'Click the "Psy Orbit" button → Create a session → the start modal shows a ready-to-copy invite link and lets you optionally clear your current queue. Share that link however you like. While a session is running, the share button in the session bar at the top copies the link again at any time.',
+    helpSec4Title: 'Joining',
+    helpSec4Body: 'Paste the invite link anywhere in Psysonic with Ctrl+V / Cmd+V — the join prompt pops up automatically. Alternatively: "Psy Orbit" → Join a session → paste into the field. If the link points to a server you have an account on, Psysonic switches for you. When you have more than one account on that server, a small picker asks which to use.',
+    helpSec5Title: 'Suggesting tracks',
+    helpSec5Body: 'In any song list: double-click a row, or right-click → "Add to Orbit session". A single click shows a hint instead of dumping the whole album into the shared queue — that\'s intentional. Explicit bulk actions like "Play All" or "Play Album" ask for confirmation first and then append (never replace).',
+    helpSec6Title: 'The shared queue',
+    helpSec6Body: "The queue shows the host's upcoming tracks — visible to everyone. Incoming bulk additions are always appended, so guest suggestions aren't lost. Auto-shuffle reorders the queue periodically (configurable: 1 / 5 / 10 / 15 / 30 min). If your playback drifts away from the host, the \"Catch up\" button in the session bar jumps you back to the host's live position.",
+    helpSec7Title: 'Approvals',
+    helpSec7Body: 'By default, guest suggestions need manual approval — they appear in an "Approvals" strip at the top of the queue panel with accept / decline buttons. Auto-approve can be turned on in the session settings so everything lands straight away.',
+    helpSec8Title: 'Participants and settings',
+    helpSec8Body: 'Open the settings icon in the session bar for shuffle cadence, auto-approve, and the "Shuffle now" shortcut. Click the participants count to see who\'s connected — kick (can re-join via the link) or ban (locked out for the session). Guests see the participant list too, but read-only.',
+    helpSec9Title: 'Ending the session',
+    helpSec9Body: "Host X → confirm dialog → session closes for everyone and the server playlists are cleaned up automatically. Guest X → the guest leaves, the session keeps running. If the host goes quiet for 5 minutes the guest auto-leaves with a notice; short reconnects within that window are invisible.",
     participantsInviteLabel: 'Invite link',
     participantsCountLabel: '{{count}} in session',
     participantsHost: 'host',