feat: allow renaming history entries

[mvanhorn]

History entries get random slug names, making it hard to find a specific save point. This adds a rename button so you can give entries meaningful names.

Click the edit icon next to any entry name. The name turns into a text input. Hit Enter or click away to save. Escape to cancel. The new name persists to localStorage through the existing store.

Two files changed:

• history.ts: added renameHistoryEntry(id, newName)
• History.svelte: added edit icon button + inline text input

Per @sidharthv96's UX spec in #967.

Fixes #967

This contribution was developed with AI assistance (Codex).

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[sidharthv96]

Hi @mvanhorn,

PR looks good, need some more tweaks to handle edge cases.

• Make the field required to stop empty names
• Tweak css to handle very long names that push other things out. Use ellipsis.
• Move the edit button to the right side of the name text, and make it a bit smaller.
• Add tests

[mvanhorn]

Addressed in 47649f6:

• Rename input has required + trim guard so empty names are rejected at both UI and store level
• Long names truncate with ellipsis at 150px, full name visible on hover via title
• Edit icon moved inline next to the name text, smaller (3.5x3.5)
• Added 3 rename tests covering manual, auto, and targeted-entry-only scenarios
• Also fixed a pre-existing eslint no-navigation-without-resolve error on the revision link by adding rel="external"

[sidharthv96]

Can you please move the edit icon to the right of the title?
Similar to how it's in GitHub

[sidharthv96]

Long names truncate with ellipsis at 150px, full name visible on hover via title

Instead of hardcoding to 150px, please use flex, so that it will grow as required within the available space. Now a lot of space is wasted by the truncation.

[mvanhorn]

Addressed both in 9c4acc3:

• Edit icon is now inline to the right of the name text
• Replaced the hardcoded 150px max-width with flex layout -- the name grows within available space and only truncates with ellipsis when it actually needs to

[sidharthv96]

Replaced the hardcoded 150px max-width with flex layout -- the name grows within available space and only truncates with ellipsis when it actually needs to

Current behaviour is pushing the other icons off the screen, forcing a scroll, it is not truncating with ellipsis.

[mvanhorn]

Fixed in c15c0f2 - the min-w-fit on the history list container was preventing the name from being constrained, so it grew past the available space instead of truncating. Removed that and added overflow-hidden to the name row so ellipsis kicks in properly.