Refactor Exchange APIs

[kghost]

Summary of Changes

• Use more modern C++ code style (for-loop)
• Change PeerConnectionState in SecureSessionMgrDelegate API to const
• Remove unnessasary callback in Transport::PeerConnections

[github-actions]

Size increase report for "nrfconnect-example-build" from 188a35f

File	Section	File	VM
chip-lock.elf	shell_root_cmds_sections	4	4
chip-lock.elf	bss	0	-1
chip-lock.elf	text	-20	-20
chip-lock.elf	[LOAD #3 [RW]]	0	-31
chip-lighting.elf	shell_root_cmds_sections	4	4
chip-lighting.elf	bss	0	-5
chip-lighting.elf	text	-20	-20
chip-lighting.elf	[LOAD #3 [RW]]	0	-27

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

Comparing ./master_artifact/chip-shell.elf and ./pull_artifact/chip-shell.elf:

sections,vmsize,filesize

Comparing ./master_artifact/chip-lock.elf and ./pull_artifact/chip-lock.elf:

sections,vmsize,filesize
.debug_loc,0,72
.debug_abbrev,0,68
.debug_info,0,55
shell_root_cmds_sections,4,4
bss,-1,0
.shstrtab,0,-2
.strtab,0,-2
text,-20,-20
[LOAD #3 [RW]],-31,0
.debug_line,0,-51
.debug_ranges,0,-56
.debug_str,0,-224

Comparing ./master_artifact/chip-lighting.elf and ./pull_artifact/chip-lighting.elf:

sections,vmsize,filesize
.debug_loc,0,72
.debug_abbrev,0,68
.debug_info,0,55
shell_root_cmds_sections,4,4
.shstrtab,0,-2
.strtab,0,-2
bss,-5,0
text,-20,-20
[LOAD #3 [RW]],-27,0
.debug_line,0,-51
.debug_ranges,0,-56
.debug_str,0,-224

[github-actions]

Size increase report for "esp32-example-build" from 188a35f

File	Section	File	VM
chip-all-clusters-app.elf	.flash.rodata	-4	-4
chip-all-clusters-app.elf	.dram0.bss	0	-8
chip-all-clusters-app.elf	.dram0.data	-8	-8

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

Comparing ./master_artifact/chip-all-clusters-app.elf and ./pull_artifact/chip-all-clusters-app.elf:

sections,vmsize,filesize
.debug_abbrev,0,57
.debug_info,0,36
[Unmapped],0,12
.debug_loc,0,3
.xt.prop._ZN4chip8Encoding12LittleEndian7Write32ERPhj,0,1
.flash.rodata,-4,-4
.dram0.bss,-8,0
.dram0.data,-8,-8
.debug_ranges,0,-16
.debug_line,0,-42
.debug_str,0,-251