Add libmcu and unit test framework

[onkwon]

No description provided.

[github-actions]

           text	   data	    bss	    dec	    hex	filename
current  177721	  50704	 371141	 599566	  9260e	build/template.elf
base          0	      0	      0	      0	      0	build/template.elf
diff     177721   50704  371141

[github-actions]

Found no defects in start.c
Found no defects in main.c
[MEDIUM] /__w/template-esp32/template-esp32/src/main.c:21:2: the value returned by this function should be used [cert-err33-c]
  fwrite(buf, len, 1, stdout);
  ^

Found 1 defect(s) in main.c


----==== Severity Statistics ====----
----------------------------
Severity | Number of reports
----------------------------
MEDIUM   |                 1
----------------------------
----=================----

----==== Checker Statistics ====----
-------------------------------------------
Checker name | Severity | Number of reports
-------------------------------------------
cert-err33-c | MEDIUM   |                 1
-------------------------------------------
----=================----

----==== File Statistics ====----
-----------------------------
File name | Number of reports
-----------------------------
main.c    |                 1
-----------------------------
----=================----

----======== Summary ========----
---------------------------------------------
Number of processed analyzer result files | 6
Number of analyzer reports                | 1
---------------------------------------------
----=================----

[github-actions]

-en ```

text data bss dec hex filename
current 177733 50704 371141 599578 9261a build/template.elf
base 0 0 0 0 0 build/template.elf
diff 177733 50704 371141-e

[github-actions]

Found no defects in start.c
[MEDIUM] /__w/template-esp32/template-esp32/src/main.c:21:11: narrowing conversion from 'unsigned int' to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
  int rc = fwrite(buf, len, 1, stdout);
           ^

Found 1 defect(s) in main.c


----==== Severity Statistics ====----
----------------------------
Severity | Number of reports
----------------------------
MEDIUM   |                 1
----------------------------
----=================----

----==== Checker Statistics ====----
-------------------------------------------------------------
Checker name                   | Severity | Number of reports
-------------------------------------------------------------
bugprone-narrowing-conversions | MEDIUM   |                 1
-------------------------------------------------------------
----=================----

----==== File Statistics ====----
-----------------------------
File name | Number of reports
-----------------------------
main.c    |                 1
-----------------------------
----=================----

----======== Summary ========----
---------------------------------------------
Number of processed analyzer result files | 6
Number of analyzer reports                | 1
---------------------------------------------
----=================----

[github-actions]

           text	   data	    bss	    dec	    hex	filename
current  177733	  50704	 371141	 599578	  9261a	build/template.elf
base     159173	  46760	 367669	 573602	  8c0a2	build/template.elf
diff      18560    3944    3472

[github-actions]

Found no defects in main.c
[MEDIUM] /__w/template-esp32/template-esp32/src/main.c:21:11: narrowing conversion from 'unsigned int' to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
  int rc = fwrite(buf, len, 1, stdout);
           ^

Found 1 defect(s) in main.c

Found no defects in start.c

----==== Severity Statistics ====----
----------------------------
Severity | Number of reports
----------------------------
MEDIUM   |                 1
----------------------------
----=================----

----==== Checker Statistics ====----
-------------------------------------------------------------
Checker name                   | Severity | Number of reports
-------------------------------------------------------------
bugprone-narrowing-conversions | MEDIUM   |                 1
-------------------------------------------------------------
----=================----

----==== File Statistics ====----
-----------------------------
File name | Number of reports
-----------------------------
main.c    |                 1
-----------------------------
----=================----

----======== Summary ========----
---------------------------------------------
Number of processed analyzer result files | 6
Number of analyzer reports                | 1
---------------------------------------------
----=================----

[github-actions]

           text	   data	    bss	    dec	    hex	filename
current  177729	  50704	 371141	 599574	  92616	build/template.elf
base     159173	  46760	 367669	 573602	  8c0a2	build/template.elf
diff      18556    3944    3472