feat: use external browser with notification content links

[zaniluca]

No description provided.

[sentry]

Bug: The regex /^[data:text, about:blank]/ uses a character class [] instead of alternation |. This incorrectly keeps many external URLs inside the WebView.
_{Severity: HIGH}

Suggested Fix

Replace the incorrect character class-based regex with one that uses alternation to match the full schemes. The regex should be changed to /^(data:|about:blank)$/ to correctly match data: or about:blank URLs.

Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent.
Verify if this is a real issue. If it is, propose a fix; if not, explain why it's not
valid.

Location: src/screens/NotificationDetail.tsx#L61

Potential issue: The regular expression on line 61 uses a character class `[]` which
matches any single character within the set, rather than the intended string literals.
The logic is designed to open URLs in an external browser unless they match the pattern.
Because of the incorrect regex, any URL starting with characters like 'd', 'a', 't', or
'e' (e.g., `docs.gitlab.com`) will be incorrectly trapped within the WebView instead of
opening externally. This defeats the primary purpose of the feature, which is to open
notification links in an external browser.

_{Did we get this right? 👍 / 👎 to inform future reviews.}