Add runtime_profile

[herzmx]

This PR adds a runtime profile service (runtime_profile) that lets users remap
buttons and configure auto-fire on the fly without reflashing the firmware.

Changes

New runtime_profile service (src/core/services/profiles/)

Runtime button-mapping service with three trigger modes, all operating with profile-switch combo:

Trigger	Activation	Behavior
A — Sequential mode	Hold SELECT alone for 2s	Press buttons one by one to map them in order to fixed outputs, START cancel/clear runtime profile
B — Tap mode	Hold START + 2 eligible buttons for 2s	Tap a button N times to map it to output slot N, START save current map, SELECT cancel/clear runtime profile
C — Auto-fire mode	Hold START + 1 eligible button for 2s	Tap the target button 1–6 times to select frequency, START save, SELECT cancel/clear auto-fire

Available auto-fire frequencies: 30 Hz, 20 Hz, 15 Hz, 12 Hz, 10 Hz, 7.5 Hz
(tap sequence timeout: 800 ms).

Auto-fire support in the profile system (src/core/services/profiles/profile.h/c)

• New autofire_period_ms field in button_map_entry_t
• New autofire_start_ms[22] array in profile_output_t — preserved across calls
  (excluded from the memset reset)
• New MAP_AUTOFIRE(in, out, period_ms) macro and AUTOFIRE_*HZ constants
• profile_apply() drives auto-fire via time-based oscillation: button ON during
  the first half of each period, OFF during the second half
  • (elapsed % period) < (period / 2)

usb2neogeo integration (src/apps/usb2neogeo/)

• Runtime profile config for 6 NeoGeo outputs (B1–B6) with a face + shoulder as input
  mask
• app.c calls runtime_profile_init() at startup

gpio_device.c refactor

• Extracted gpio_apply_output() helper that transparently selects the runtime profile
  or falls back to the active normal profile
• Tap callback now stores all analog axes (lx, ly, rx, ry, l2, r2, rz) for full
  re-application
• Periodic re-apply loop in gpio_device_task() so auto-fire oscillates even when the
  controller stops sending USB reports while a button is held
• Profile-switch combo is suppressed during mapping mode; switching profiles normally
  clears the runtime map