fix(i18n): fix ~80 broken/placeholder strings in en.ts #2143

Summary

The English translation file (app/src/lib/i18n/en.ts) accumulated a large number of issues from the i18n migration auto-merge, including raw code leaked into string values, inverted labels, capitalization errors, and placeholder stubs that were never filled in.

Issues fixed

Bug fixes (wrong / inverted values)

• common.loading — 'loading…' → 'Loading…' (capital L)
• rewards.community.locked — 'Unlocked' → 'Locked'
• settings.cron.jobs.paused — 'Enabled' → 'Paused'
• settings.ai.addProvider / saveChanges — both showed 'Saving…'; corrected to 'Add Provider' / 'Save Changes'
• settings.autocomplete.completionStyle.clearHistory — 'Clearing…' → 'Clear History'
• settings.billing.autoRecharge.saveSettings — 'Saving…' → 'Save Settings'
• settings.localModel.status.showErrorDetails / showInstallErrorDetails — both said 'Hide error details'; fixed to 'Show error details'
• webhooks.tunnels.inactive — 'Active' → 'Inactive'
• webhooks.tunnels.enableEcho — 'Remove Echo' → 'Enable Echo'

Raw code / template literals leaked into string values

• settings.cron.jobs.loadingRuns/removing/runningNow/viewRuns — had core-runs:${job.id} etc.
• settings.ai.connectProvider / editProvider — had ${} {label} / Edit ${initial.label}
• settings.billing.payAsYouGo.opening — had $${amount.toFixed(2)}
• settings.billing.autoRecharge.setDefault — had ':'
• channels.discord.picker.category — had ${} {categoryId}
• rewards.referralSection.linkedCode — had '+ .replace('
• skills.meetingBots.comingSoon/sendTo — had ${selected.label}
• notifications.card.importanceTitle — had raw JS expression
• autocomplete.completionStyle.acceptedCompletion/s — had full JS template literals with ternary
• upsell.usageLimit.bodyBudget/bodyRate/resetsIn — had raw JS fragments
• app.openhumanLink.defaultBody — truncated mid-sentence fragment
• skills.setup.screenIntel.enableDesc — truncated string starting mid-word

~50 placeholder stubs filled in — 'Heading', 'Body', 'Perk1'–'Perk4', 'Desc', 'Title', 'Subtitle', and similar values that were never replaced after the auto-merge

Capitalization

• ollama → Ollama, Llm → LLM, Oauth timeout → OAuth timed out, Macos → macOS, ComposeIO → Composio (typo), ids → IDs

Stale copy

• home.statusCoreUnreachable still referenced "sidecar" (removed in PR fix(core,cef): run core in-process and stop orphaning CEF helpers on Cmd+Q #1061); updated to say "The OpenHuman core isn't responding."

Test plan

• pnpm typecheck passes
• Spot-check the affected UI areas (notifications empty state, billing, cron jobs, skills, upsell banners)