GPS Profile in Position config; Position Flags deprecated (protobufs#749)

[jamesarich]

Tracks the Android side of meshtastic/protobufs#749 (open, approved incl. by @jamesarich, CI currently red). Adds PositionConfig.GpsProfile (MANUAL = 0, pedestrian / vehicle / fixed …) and marks every PositionFlags member [deprecated = true]. Firmware derives update interval, broadcast interval, smart-broadcast min interval/distance and flags from the profile.

• blocked on protobufs#749 merge + protobufs bump
• PositionConfigScreen.kt: add a profile selector; when profile != MANUAL collapse the five derived fields (intervals, smart-broadcast, flags) into a read-only summary
• keep the manual path intact for profile == MANUAL (balloons/boats/fixed-manual users)
• hide or read-only the deprecated Position Flags editor behind MANUAL
• Capabilities gate on firmware version so old firmware keeps the current UI