Allow Partial URL Parameters

[kylerisse]

Fixes #55

Description of PR

Partial date parameters supplied in the URL will now merge with actual values from now to make development more enjoyable. Because time shifting is mainly for development there is no attempt to bound integer values and they simply pass them straight through to Date library for better or worse. Non-numbers are ignored. Thank you to @carlynlee for working on this.

Previous Behavior

Every URL parameter was required to create a time shifted customer date. (year, month, day, hour, minute)

New Behavior

Developer can choose to omit certain values and the result with be what is expected. For example http://localhost/?month=3 would only change the month but keep the current year, day, hour, and minute. This works for any combination of values.

Tests

• mainly UI testing

[sarcasticadmin]

Builds fine and runs great:

$ ./result/bin/go-signs
2026/02/10 21:23:34 Updating Schedule from https://www.socallinuxexpo.org/scale/23x/signs
2026/02/10 21:23:34 Listening on :2017
2026/02/10 21:23:36 Invalid DrupalNode {PostgreSQL Hands-On Training Day    Ryan Booz, Devrim Gunduz, Elizabeth Christensen Pos
tgreSQL A full PostgreSQL training day adjacent to the SCaLE LA event. 6 hours total, running for a full day as a single track
(with 90 minute lunch break). Attendees can attend some or all of the event. Aimed both at new Postgres users and those migrati
ng from other db systems. 
} (error: invalid StartTime)
2026/02/10 21:23:36 Schedule updated with 272 sessions, hash: df55094754d8b9a84096b2bb9e8793840f639bc82535fd4d06a24545c9e492af
[GIN] 2026/02/10 - 21:23:59 | 200 |    2.245719ms |       127.0.0.1 | GET      "/?year=2025&month=3&day=8&hour=1&minute=53"
[GIN] 2026/02/10 - 21:23:59 | 200 |     201.167µs |       127.0.0.1 | GET      "/assets/index-C11fsQvG.css"
[GIN] 2026/02/10 - 21:23:59 | 200 |       995.8µs |       127.0.0.1 | GET      "/assets/index-DjfHA5we.js"
[GIN] 2026/02/10 - 21:23:59 | 200 |     270.368µs |       127.0.0.1 | GET      "/assets/wifi-DhUPXLyX.png"
[GIN] 2026/02/10 - 21:23:59 | 200 |     835.329µs |       127.0.0.1 | GET      "/assets/logo-B5b-HI3O.png"
[GIN] 2026/02/10 - 21:23:59 | 200 |     153.819µs |       127.0.0.1 | GET      "/sponsors/all"
[GIN] 2026/02/10 - 21:23:59 | 200 |    1.913815ms |       127.0.0.1 | GET      "/schedule"
[GIN] 2026/02/10 - 21:23:59 | 404 |      46.407µs |       127.0.0.1 | GET      "/favicon.ico"
[GIN] 2026/02/10 - 21:23:59 | 200 |     183.715µs |       127.0.0.1 | GET      "/assets/noc-penguin-D40Kt-Pp.png"
[GIN] 2026/02/10 - 21:23:59 | 200 |     108.804µs |       127.0.0.1 | GET      "/sponsors/images/microsoft.png"
...

Partial time shifting works great too: http://127.0.0.1:2017/?year=2026&month=3&day=7 (ignore my UTC timezone):