Adopt ensure_lib_deps() in all remaining non-ESP32 orchestrators

[zackees]

Background

PR #1291 (fixes #1276) added the ensure_lib_deps() helper to
crates/fbuild-build-engine/src/pipeline/library.rs and wired it into the
AVR orchestrator. The helper downloads registry/remote lib_deps entries
before the compiler is created, so library include directories are available
during compilation and their archives are linked into the firmware.

What's left

Eleven orchestrators that use run_sequential_build_with_libs() still pass
&[] as extra_link_inputs and never download lib_deps. Each needs
the same 3-step integration:

1. Read lib_deps / lib_ignore from config
2. Call pipeline::ensure_lib_deps() before creating the compiler (use a
   temp compiler to get c/cxx flags)
3. Add the returned include dirs to the compiler and pass the archives as
   extra_link_inputs

Orchestrators to fix

Orchestrator	File
Teensy	crates/fbuild-build-arm/src/teensy/orchestrator.rs
STM32	crates/fbuild-build-arm/src/stm32/orchestrator/mod.rs
STM32 (Arduino Mbed)	crates/fbuild-build-arm/src/stm32/orchestrator/arduino_mbed.rs
RP2040	crates/fbuild-build-arm/src/rp2040/orchestrator.rs
SAM	crates/fbuild-build-arm/src/sam/orchestrator.rs
CH32V	crates/fbuild-build-mcu/src/ch32v/orchestrator.rs
ESP8266	crates/fbuild-build-esp/src/esp8266/orchestrator.rs
NRF52	crates/fbuild-build-arm/src/nrf52/orchestrator.rs
Renesas	crates/fbuild-build-arm/src/renesas/orchestrator.rs
Silabs	crates/fbuild-build-arm/src/silabs/orchestrator.rs
Apollo3	crates/fbuild-build-arm/src/apollo3/orchestrator.rs
NXP LPC	crates/fbuild-build-arm/src/nxplpc/orchestrator.rs

Reference

The AVR integration in PR #1291 is the canonical example — see the diff at
crates/fbuild-build-mcu/src/avr/orchestrator.rs. The pattern is mechanical:
build a temp compiler for flags, call ensure_lib_deps(), extend
include_dirs, pass lib_archives to run_sequential_build_with_libs.

Already working

• ESP32 — already calls ensure_libraries() directly (predates this PR)
• AVR — wired in fix(avr): download registry lib_deps before compilation #1291