Improve session-management commands in chip-tool.

[bzbarsky-apple]

• Move them into a separate "sessionmanagement" bit, to make them more discoverable.
• Add a command to expire the local CASE sessions for a given node id.
• Rename close-session to send-close-session.
• Add an option to control whether send-close-session also expires the local session (defaulting to true).

[github-actions]

PR #26404: Size comparison from c984f0b to 650e26b

Decreases (1 build for cc32xx)

platform	target	config	section	c984f0b	650e26b	change	% change
cc32xx	lock	CC3235SF_LAUNCHXL	.debug_info	19609757	19609756	-1	-0.0

Full report (1 build for cc32xx)

platform	target	config	section	c984f0b	650e26b	change	% change
cc32xx	lock	CC3235SF_LAUNCHXL		0	0	0	0.0
			(read only)	605090	605090	0	0.0
			(read/write)	204164	204164	0	0.0
			.ARM.attributes	44	44	0	0.0
			.ARM.exidx	8	8	0	0.0
			.bss	197576	197576	0	0.0
			.comment	206	206	0	0.0
			.data	1468	1468	0	0.0
			.debug_abbrev	957621	957621	0	0.0
			.debug_aranges	101136	101136	0	0.0
			.debug_frame	341512	341512	0	0.0
			.debug_info	19609757	19609756	-1	-0.0
			.debug_line	2666632	2666632	0	0.0
			.debug_line_str	513	513	0	0.0
			.debug_loc	33340	33340	0	0.0
			.debug_loclists	1489225	1489225	0	0.0
			.debug_ranges	4984	4984	0	0.0
			.debug_rnglists	94315	94315	0	0.0
			.debug_str	3108982	3108982	0	0.0
			.ramVecs	780	780	0	0.0
			.resetVecs	64	64	0	0.0
			.rodata	104354	104354	0	0.0
			.shstrtab	265	265	0	0.0
			.stack	2048	2048	0	0.0
			.strtab	483384	483384	0	0.0
			.symtab	287328	287328	0	0.0
			.text	498612	498612	0	0.0

[github-actions]

PR #26404: Size comparison from c984f0b to 38ed5e0

Decreases (1 build for cc32xx)

platform	target	config	section	c984f0b	38ed5e0	change	% change
cc32xx	lock	CC3235SF_LAUNCHXL	.debug_info	19609757	19609756	-1	-0.0

Full report (1 build for cc32xx)

platform	target	config	section	c984f0b	38ed5e0	change	% change
cc32xx	lock	CC3235SF_LAUNCHXL		0	0	0	0.0
			(read only)	605090	605090	0	0.0
			(read/write)	204164	204164	0	0.0
			.ARM.attributes	44	44	0	0.0
			.ARM.exidx	8	8	0	0.0
			.bss	197576	197576	0	0.0
			.comment	206	206	0	0.0
			.data	1468	1468	0	0.0
			.debug_abbrev	957621	957621	0	0.0
			.debug_aranges	101136	101136	0	0.0
			.debug_frame	341512	341512	0	0.0
			.debug_info	19609757	19609756	-1	-0.0
			.debug_line	2666632	2666632	0	0.0
			.debug_line_str	513	513	0	0.0
			.debug_loc	33340	33340	0	0.0
			.debug_loclists	1489225	1489225	0	0.0
			.debug_ranges	4984	4984	0	0.0
			.debug_rnglists	94315	94315	0	0.0
			.debug_str	3108982	3108982	0	0.0
			.ramVecs	780	780	0	0.0
			.resetVecs	64	64	0	0.0
			.rodata	104354	104354	0	0.0
			.shstrtab	265	265	0	0.0
			.stack	2048	2048	0	0.0
			.strtab	483384	483384	0	0.0
			.symtab	287328	287328	0	0.0
			.text	498612	498612	0	0.0