fix: verify macOS 26 manual fan control

[naufaldi]

What Change

• prevent the browser IPC mock from loading in tauri dev
• require helper protocol v2 so stale installed helpers are upgraded instead of trusted
• probe both F*Md and lowercase F*md mode keys for newer Apple Silicon Macs
• require Manual-mode, target-register, and measured-RPM verification before reporting success
• verify Auto/System mode after restoration
• bump FanGuard to 0.1.0-beta.7

Why Change

On macOS 26 / Mac17,2, real telemetry was mixed with mocked write commands during Tauri development. The old helper could echo F0Tg while the fan stayed under automatic control, producing a false Applied message. This Mac also exposes the case-sensitive lowercase F0md mode key rather than F0Md.

Impact

Manual control now fails closed unless the helper is compatible, Manual mode persists, and measured fan RPM responds. Auto restoration is verified.

Verification

• pnpm biome:check
• pnpm test (63 passed)
• pnpm exec svelte-check --tsconfig ./tsconfig.json
• pnpm playwright:test (6 passed)
• pnpm build
• cargo check
• cargo clippy -- -D warnings
• cargo test (115 passed, 1 ignored in binary; 18 passed in library)
• macOS 26 hardware: actual fan moved from ~2,506 RPM to 3,509 RPM for a 3,500 RPM target, then returned to ~2,506 RPM after Auto restoration