feat(mobile): add thread title regeneration - #6253

💭 Looking at this PR, it's mostly mobile UI code in React with the correct Effect imports using the subpath namespace. There are no service definitions or dependency injection issues in the touched code, so I need to verify whether threadEnvironment.updateMetadata exists on the server side and if the mobile implementation needs anything else for Effect service conventions.… I'm reviewing the PR to check for Effect service violations—it's pure React/UI code using only Cause.squash from the effect library with proper imports, so there are no issues. But I'm not…