M7.2.7: replace src/components/DrawerContent.tsx with wp-native-shell DrawerShell

[chubes4]

Scope

Delete src/components/DrawerContent.tsx and app/(drawer)/_layout.tsx (the EC drawer + browser-handoff implementation). Drawer is now provided by wp-native-shell via <DrawerShell/>, mounted inside <WPNativeApp/> (M7.2.5).

Why

<WPNativeApp/> already wires <DrawerShell sections={config.navigation.sections}/>. The custom drawer is dead.

Files affected

DELETE: src/components/DrawerContent.tsx (~200 lines)
DELETE: app/(drawer)/_layout.tsx (~50 lines)
DELETE: app/(drawer)/feed.tsx (?) — keep as a screen, but it'll get registered through config.navigation

The screens that lived under app/(drawer)/ need to either:

• Stay as Expo Router routes and be referenced by config.navigation.sections[].screen, OR
• Be deleted and replaced by ability-driven AbilityList screens (M6.1)

For v0.1 dogfood, the simplest path is: keep the existing screen files, reference them by screen: in config. The ability-driven path is a follow-up.

Browser handoff

The EC drawer hardcodes extrachill.com / extrachill.link host checks (per audit issue #19). After this PR, that logic lives in wp-native-shell's useBrowserHandoff() reading from config.browserHandoff.handoffHosts / excludeHosts. Closes #19 as part of this work.

Sequencing

After M7.2.5 (<WPNativeApp/> mounted). The drawer config's section list is the API contract that determines what stays in app/(drawer)/ and what becomes a screen: reference.

Acceptance

• src/components/DrawerContent.tsx deleted
• app/(drawer)/_layout.tsx deleted
• Hardcoded extrachill.com / extrachill.link host checks removed
• All sections render correctly via config.navigation.sections
• Browser handoff still works for *.extrachill.com (now via config)
• Closes Decouple: hardcoded extrachill.com / extrachill.link in browser handoff #19

References

• SHELL.md M5.3
• Audit #19
• Tracking #27