12bbdc77

Add renderTemplate wrapper to eliminate ExecuteTemplate boilerplate

Every page handler repeated the same render-then-handle-error block after
building its template data. Extract it into a single renderTemplate helper
in templates.go and route all 7 call sites through it.

The helper renders into a buffer first, so a mid-render failure becomes a
clean 500 instead of a partially written response.

renderLogin's status parameter was always http.StatusOK, so drop it and
route renderLogin through the same wrapper, leaving no special cases.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Agent Instructions

Each run corresponds to one flake attribute. Click a run for its logs and status.

Example: https://nix-ci.com/cb:mtlynch:little-moments/template-wrapper/12bbdc77c8bb31ce8a6666ada2bcc51fb0953e08/988bc0e1-0767-4555-958b-13690f19236c

Wait for suite to complete:

curl --netrc -N https://nix-ci.com/cb:mtlynch:little-moments/template-wrapper/12bbdc77c8bb31ce8a6666ada2bcc51fb0953e08/wait

This page is also available in machine-friendly formats. Request one with the Accept header:

• curl --netrc -H 'Accept: application/json' https://nix-ci.com/cb:mtlynch:little-moments/template-wrapper/12bbdc77c8bb31ce8a6666ada2bcc51fb0953e08
• curl --netrc -H 'Accept: text/markdown' https://nix-ci.com/cb:mtlynch:little-moments/template-wrapper/12bbdc77c8bb31ce8a6666ada2bcc51fb0953e08

For more instructions, fetch https://nix-ci.com/instructions .