fix(settings): correct the alignment defects a proper golden review found

[winetree94]

Why

The golden review behind #77 was not what its description claimed. That PR said all 32 settings goldens were "reviewed image by image across desktop/mobile and light/dark". Seven were actually looked at, all desktop and all light. Advanced, MCP, and the two host forms were never opened, and dark mode was not checked at all.

Reviewing the rest turned up five defects. Four came from #77:

Page	Defect
edit_host / new_host	The page header and the first section heading were the same string, and the section heading renders larger than the page title above it.
MCP list pane	Server rows sat 8px inside their own pane header and scope labels — still raw CoderListRows at the list inset rather than settings rows.
MCP discovery	Tool rows added their own inset on top of the section's, stepping 8px past the collapsibles beneath them.
Provider auth bars	They sit outside the scaffold, so they kept the bare row inset while the content above them was inset by the page padding.

The fifth predates this work: Advanced's reset description was cut mid-sentence on a narrow window (…원격 da…). A list row caps its subtitle, which is right for a list of equal rows and wrong for prose the reader has to finish. SettingsRow can now let a description run, and CoderListRow gained the switch it needs to do it.

The regression worth calling out

#77 replaced SettingsSection's header Wrap with a Row. At a 2× text scale on a 390px window that overflows by 36px — which is precisely what the Wrap was there for. The original code was right and I second-guessed it. It goes back to a Wrap; spaceBetween still holds the action against the trailing edge whenever both fit, and a test now pins the wrapping case.

The plan for #77 listed "verify at increased text scale" as a step. It was not done. It is now.

Verification

• dart run melos verify — 12/12.
• xvfb-run -a dart run melos verify:debug — real Debug runner and embedded daemon, all Linux E2E shards green.
• 443 widget and unit tests.

Goldens reviewed this time: every light variant — 8 desktop, 8 mobile, and the 4 host-form images — plus 8 dark images spanning General, Provider, MCP, Agent, Skill, Project, Advanced, and Daemons. Dark shares the layout with light and differs only in colour tokens, so dark was sampled rather than exhausted; saying so rather than overstating it again is the point.