test: add unit tests for keyboard key parsing

[ZayanKhan-12]

Why

src/utils/keyboard.ts (parseKey) validates and parses the user-supplied key argument for the press_key tool, so it is a small but agent-facing input-validation path. Its only coverage so far was a handful of inline assertions inside tests/tools/input.test.ts. This PR gives the module a dedicated unit test file under tests/utils/ (alongside files.test.ts and url.test.ts), moves the existing inline assertions there, and expands coverage.

Coverage

• Single keys (Enter, Escape, F5, 5, Numpad5, KeyA, a, A, ' ', \r, \n) and lone modifiers (Shift, Control, Meta)
• Primary key returned first, followed by modifiers in original order (Control+Shift+P → ['P', 'Control', 'Shift'], Alt+Control+Delete vs Control+Alt+Delete)
• Literal plus as a key (+, Shift++, Control+Shift++)
• Trailing separator is ignored (Shift+ → ['Shift'], ++ → ['+'])
• Case sensitivity (Shift+a vs Shift+A; shift+a and ENTER throw)
• No whitespace trimming (Shift + a, Enter throw)
• Invalid key names throw with the <key> is invalid. Valid keys are: ... message shape (including NotAKey+Enter and +a)
• Empty input throws Key could not be parsed.
• Duplicate keys throw (Shift+Shift, Control+a+Control, a+a)

No src/ changes; the tests assert current behavior. One observation (not changed here): a trailing + after a valid key is silently dropped (Shift+ parses as just Shift), which may or may not be intended.

Testing

• npm run build — clean
• node scripts/test.js tests/utils/keyboard.test.ts tests/tools/input.test.ts — all pass (exit 0)
• npm run test:no-build — only failures were the known Timeout uninstalling extension flakes in console/extensions/pages; re-ran node scripts/test.js tests/tools/console.test.ts tests/tools/extensions.test.ts tests/tools/pages.test.ts in isolation — all pass (exit 0)
• npm run check-format — eslint and prettier clean

🤖 Generated with Claude Code

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