fix(workspace): harden Vela billing proxy boundaries #17112

Job	Run time
Resolve runner profiles	11s
Detect validation scopes	13s
Static gate	15s
Workspace unit tests	1m 33s
Preflight	3m 42s
E2E Vitest	6m 9s
UI P0 (workspace-restoration)	9m 46s
UI P0 (entry-settings)	12m 24s
UI P0 (project-workspace)	15m 1s
UI P0 (project-runtime)	7m 26s
Web workspace tests	0s
Playwright critical (${{ matrix.group }})	0s
Playwright visual (${{ matrix.name }})	0s
Windows tools-pack payload tests	0s
Validate workspace	2s
Runtime summary	4s
	56m 46s

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