Improve the Darwin logging when we cancel dns-sd browse/resolve operations.

[bzbarsky-apple]

Right now we are treating those as "timeout" and logging that, which really confuses people reading the logs. We should log them as cancellations instead.

There's no obvious kDNSServiceErr_* value for "cancelled", so allow doing GenericContext::Finalize with a CHIP_ERROR.

[github-actions]

PR #26072: Size comparison from 2ce04b5 to 86a6d62

Decreases (3 builds for bl602, bl702, cc32xx)

platform	target	config	section	2ce04b5	86a6d62	change	% change
bl602	lighting-app	bl602+rpc	(read/write)	1396106	1396098	-8	-0.0
			.text	1062420	1062416	-4	-0.0
bl702	lighting-app	bl702+rpc	.debug_info	45206425	45206424	-1	-0.0
			.text	1032106	1032104	-2	-0.0
cc32xx	lock	CC3235SF_LAUNCHXL	.debug_info	20303348	20303346	-2	-0.0

Full report (7 builds for bl602, bl702, cc32xx, qpg)

platform	target	config	section	2ce04b5	86a6d62	change	% change
bl602	lighting-app	bl602	(read/write)	1350102	1350102	0	0.0
			.bss	87870	87870	0	0.0
			.data	9648	9648	0	0.0
			.text	1031330	1031330	0	0.0
		bl602+rpc	(read/write)	1396106	1396098	-8	-0.0
			.bss	95918	95918	0	0.0
			.data	10040	10040	0	0.0
			.text	1062420	1062416	-4	-0.0
bl702	lighting-app	bl702		0	0	0	0.0
			(read only)	3358	3358	0	0.0
			(read/write)	1179011	1179011	0	0.0
			.bleromro	6342	6342	0	0.0
			.bleromrw	124	124	0	0.0
			.boot2	328	328	0	0.0
			.bss	64617	64617	0	0.0
			.bss_psram	24368	24368	0	0.0
			.comment	48	48	0	0.0
			.data	3952	3952	0	0.0
			.debug_abbrev	1549090	1549090	0	0.0
			.debug_aranges	134488	134488	0	0.0
			.debug_frame	494264	494264	0	0.0
			.debug_info	4071586	4071586	0	0.0
			.debug_line	5299826	5299826	0	0.0
			.debug_loc	3433121	3433121	0	0.0
			.debug_ranges	374648	374648	0	0.0
			.debug_str	3593059	3593059	0	0.0
			.hbn	536	536	0	0.0
			.hbn_noinit	260	260	0	0.0
			.init	342	342	0	0.0
			.init_array	140	140	0	0.0
			.psram	0	0	0	0.0
			.riscv.attributes	47	47	0	0.0
			.rodata	105920	105920	0	0.0
			.rsvd	2960	2960	0	0.0
			.sha_ocram	72	72	0	0.0
			.shstrtab	304	304	0	0.0
			.stack	2048	2048	0	0.0
			.strtab	573293	573293	0	0.0
			.symtab	174176	174176	0	0.0
			.tcm_data	28	28	0	0.0
			.tcmcode	3358	3358	0	0.0
			.text	959120	959120	0	0.0
		bl702+rpc		0	0	0	0.0
			(read only)	3358	3358	0	0.0
			(read/write)	1267175	1267175	0	0.0
			.bleromro	6342	6342	0	0.0
			.bleromrw	124	124	0	0.0
			.boot2	328	328	0	0.0
			.bss	72665	72665	0	0.0
			.bss_psram	24768	24768	0	0.0
			.comment	48	48	0	0.0
			.data	4504	4504	0	0.0
			.debug_abbrev	1699600	1699600	0	0.0
			.debug_aranges	142696	142696	0	0.0
			.debug_frame	522096	522096	0	0.0
			.debug_info	45206425	45206424	-1	-0.0
			.debug_line	5706958	5706958	0	0.0
			.debug_loc	3633651	3633651	0	0.0
			.debug_ranges	399624	399624	0	0.0
			.debug_str	4017284	4017284	0	0.0
			.hbn	536	536	0	0.0
			.hbn_noinit	260	260	0	0.0
			.init	342	342	0	0.0
			.init_array	156	156	0	0.0
			.psram	0	0	0	0.0
			.riscv.attributes	47	47	0	0.0
			.rodata	119760	119760	0	0.0
			.rsvd	2960	2960	0	0.0
			.sha_ocram	72	72	0	0.0
			.shstrtab	304	304	0	0.0
			.stack	2048	2048	0	0.0
			.strtab	634294	634294	0	0.0
			.symtab	192576	192576	0	0.0
			.tcm_data	28	28	0	0.0
			.tcmcode	3358	3358	0	0.0
			.text	1032106	1032104	-2	-0.0
cc32xx	lock	CC3235SF_LAUNCHXL		0	0	0	0.0
			(read only)	642953	642953	0	0.0
			(read/write)	203848	203848	0	0.0
			.ARM.attributes	44	44	0	0.0
			.ARM.exidx	8	8	0	0.0
			.bss	197248	197248	0	0.0
			.comment	194	194	0	0.0
			.data	1480	1480	0	0.0
			.debug_abbrev	933129	933129	0	0.0
			.debug_aranges	87616	87616	0	0.0
			.debug_frame	301352	301352	0	0.0
			.debug_info	20303348	20303346	-2	-0.0
			.debug_line	2679969	2679969	0	0.0
			.debug_loc	2824782	2824782	0	0.0
			.debug_ranges	286208	286208	0	0.0
			.debug_str	3039567	3039567	0	0.0
			.ramVecs	780	780	0	0.0
			.resetVecs	64	64	0	0.0
			.rodata	104353	104353	0	0.0
			.shstrtab	232	232	0	0.0
			.stab	204	204	0	0.0
			.stabstr	441	441	0	0.0
			.stack	2048	2048	0	0.0
			.strtab	377533	377533	0	0.0
			.symtab	256800	256800	0	0.0
			.text	536480	536480	0	0.0
qpg	lighting-app	qpg6105+debug	(read/write)	1154764	1154764	0	0.0
			.bss	97404	97404	0	0.0
			.data	836	836	0	0.0
			.text	601860	601860	0	0.0
	lock-app	qpg6105+debug	(read/write)	1124844	1124844	0	0.0
			.bss	92548	92548	0	0.0
			.data	840	840	0	0.0
			.text	571944	571944	0	0.0

[vivien-apple]

Thanks!

[bzbarsky-apple]

Fast-tracking platform-specific change with platform owner review.