feat(i18n): Hebrew locale + full RTL support (#243)

# feat(i18n): Hebrew locale + full RTL support

## Summary

This PR adds full Hebrew (he) locale support to the UI, including a
complete translation of all user-facing strings and comprehensive RTL
layout support across all components.

## What was done

### Hebrew translation
- Full translation of all i18n message files for the `he` locale (17
translation files)
- Registered the language in the i18n system and the language picker

### RTL support
- Automatic direction detection (`dir="rtl"`) when Hebrew is selected
- Replaced physical CSS properties (`left`/`right`) with logical
equivalents (`inline-start`/`inline-end`) across the project
- Fixed resize direction, file path alignment, and textarea padding
- Fixed navigation button positioning in textarea for RTL
- Fixed scrollbar direction in RTL
- Fixed code block direction and selector alignment
- Fixed Monaco editor direction in the file viewer
- Auto-detect text direction in reasoning block (`dir="auto"` +
`unicode-bidi: plaintext`)

### Adapted components
- `session-layout` — sidebar and resize handle
- `prompt-input` — text direction and buttons
- `message-base` — message blocks and reasoning
- `message-timeline` — timeline bar
- `right-panel` — right side panel
- `tool-call` — tool call display
- `settings-screen` — settings page
- `selector` — selection component
- `instance-shell` — main shell

## New files

```
packages/ui/src/lib/i18n/messages/he/
  advancedSettings.ts
  app.ts
  commands.ts
  dialogs.ts
  filesystem.ts
  folderSelection.ts
  index.ts
  instance.ts
  loadingScreen.ts
  logs.ts
  markdown.ts
  messaging.ts
  remoteAccess.ts
  session.ts
  settings.ts
  time.ts
  toolCall.ts
```

## Suggested testing
- Switch language to Hebrew and verify all strings are translated
- Verify RTL layout is correct across all screens (session, settings,
file viewer)
- Verify that English text inside a reasoning block is displayed LTR
- Switch back to English and verify everything returns to LTR

---------

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-authored-by: Shantur Rathore <i@shantur.com>

packages/ui/src/styles/panels/right-panel.css

@@ -11,8 +11,8 @@
   content: '';
   position: absolute;
   bottom: -1px;
-  left: 0;
-  right: 0;
+  inset-inline-start: 0;
+  inset-inline-end: 0;
   height: 1px;
   background-color: var(--border-base);
   z-index: 0;
@@ -42,7 +42,7 @@
   border: 1px solid transparent;
   border-bottom: none;
   border-radius: 8px 8px 0 0;
-  margin-right: 2px;
+  margin-inline-end: 2px;
   z-index: 1;
 }
 
@@ -90,8 +90,8 @@
 .file-split-handle {
   cursor: col-resize;
   background-color: transparent;
-  border-left: 1px solid var(--border-base);
-  border-right: 1px solid var(--border-base);
+  border-inline-start: 1px solid var(--border-base);
+  border-inline-end: 1px solid var(--border-base);
   user-select: none;
   touch-action: none;
 }
@@ -148,7 +148,7 @@
   display: flex;
   flex-direction: column;
   background-color: var(--surface-secondary);
-  border-left: 1px solid var(--border-base);
+  border-inline-start: 1px solid var(--border-base);
   /* Monaco uses layered positioned elements; keep overlay well above it. */
   z-index: 200;
 }
@@ -334,6 +334,7 @@
 .monaco-viewer {
   width: 100%;
   height: 100%;
+  direction: ltr;
 }
 
 .file-viewer-empty {
@@ -459,7 +460,7 @@
 }
 
 .section-label {
-  margin-left: 2px;
+  margin-inline-start: 2px;
 }
 
 .section-info-icon {
@@ -528,7 +529,7 @@
 }
 
 .right-panel-empty--left {
-  @apply items-start justify-start text-left w-full;
+  @apply items-start justify-start text-start w-full;
 }
 
 .right-panel-empty-text {