feat: mobile keyboard input visibility - scroll inputs into view when keyboard opens

- Add KeyboardHandler module using visualViewport API for keyboard detection
- Set --keyboard-height CSS variable and toggle .keyboard-visible class
- Auto-scroll focused inputs into view after keyboard appears (350ms delay)
- Update viewport meta with interactive-widget=resizes-content for Android
- Add scroll-margin on inputs for tablet/phone breakpoints
- Resize modal-content and modal-body when keyboard visible on mobile

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

CLAUDE.md

@@ -16,7 +16,7 @@ When user says "COM":
 1. Increment version in BOTH `package.json` AND `CLAUDE.md`
 2. Run: `git add -A && git commit -m "chore: bump version to X.XXXX" && git push && npm run build && systemctl --user restart claudeman-web`
 
-**Version**: 0.1450 (must match `package.json`)
+**Version**: 0.1451 (must match `package.json`)
 
 ## Project Overview
 
@@ -24,7 +24,7 @@ Claudeman is a Claude Code session manager with web interface and autonomous Ral
 
 **Tech Stack**: TypeScript (ES2022/NodeNext, strict mode), Node.js, Fastify, node-pty, xterm.js
 
-**TypeScript Strictness** (see `tsconfig.json`): `noUnusedLocals`, `noUnusedParameters`, `noImplicitReturns`, `noImplicitOverride`, `noFallthroughCasesInSwitch`, `allowUnreachableCode: false`, `allowUnusedLabels: false`
+**TypeScript Strictness** (see `tsconfig.json`): `noUnusedLocals`, `noUnusedParameters`, `noImplicitReturns`, `noImplicitOverride`, `noFallthroughCasesInSwitch`, `allowUnreachableCode: false`, `allowUnusedLabels: false`. Note: `src/tui` is excluded from compilation (legacy/deprecated code path).
 
 **Requirements**: Node.js 18+, Claude CLI, GNU Screen