ESP: fix build issues by introducing swift component

[Lapshin]

@erhankur , this change fixes the issue with picolibc enabled that we discussed.

The root cause was adding CMAKE_C_IMPLICIT_INCLUDE_DIRECTORIES into the main target. It makes the include argument order unexpected.
When the inclusion was moved to a separate component, it respects includes from esp_libc that should be first.

IMO it's better to have swift in managed components. Could you take care of this?

Other observations:

• BridgingHeader.h can be generated automatically (include all public headers from required components)
• LED does not blink on my esp32c6 board. Even with the code before my changes

[erhankur]

@Lapshin Thanks for the PR. Led blink issue is fixed in #191

[rauhul]

I would prefer if this change moved the esp examples into an esp/ directory and the components was placed under there

[erhankur]

@Lapshin Now we have one more example. esp32-uart-echo

[Lapshin]

depends on espressif/idf-extra-components#685

[erhankur]

@Lapshin LGTM Nice cleanup. Tested all examples.