feat(13-01): add the prohibited rule and dated-download and notification masks

- lagoon.ValidateRequest supports Laravel 9 prohibited (!required, not
  implicit); with no catalog line its message is validation.prohibited
- tide compares Content-Disposition with real calendar dates masked on both
  sides; a different name, an invalid date or a one-sided date still diffs
- tide.NormalizePublications masks a Carbon +00:00 $.data.payload.created_at
  and an uncaptured positive integer $.data.payload.id as {{id}}
- the album-date test's outside-album sibling moves off payload.created_at,
  which now has its own mask
- READMEs and docs describe the rule and both masks

modules/lagoon/README.md

@@ -18,7 +18,7 @@ Postgres data layer: the shared GORM connection, per-plugin migrations, model he
 - Per-plugin migrations: `lagoon.Migrate` runs the framework's `system_files` set (`attach.Migrations`), backend admin identity set (`lagoon.BackendAdminMigrations`), `deferred_bindings` set (`lagoon.DeferredBindingMigrations`, under the `lagoon.DeferredHistoryID` history) and job-queue set (`lagoon.QueueMigrations`: River's schema pinned at `lagoon.RiverSchemaVersion`, then the `lagoon.JobsTable` record table, under the `lagoon.QueueHistoryID` history), then every `pact.HasMigrations` set in plugin activation order, each in its own `summer_migrations_<plugin_id>` history table (`lagoon.HistoryTableName`). `lagoon.RollbackLast` and `lagoon.Status` cover rollback and history.
 - Mass assignment: `lagoon.Fill` copies only allow-listed keys onto a model by GORM column name and silently drops the rest, logging each dropped key once outside production. A `json.Number` (from a decoder using `UseNumber`) fills integer, unsigned and float fields. A value that does not fit its column (a fraction, an exponent or an overflow for an integer field, or a value of the wrong type) is a `lagoon.FillTypeError` naming the key, so a caller can answer it as a validation failure on that field. `lagoon.HasFillable` and `lagoon.HasHidden` are the Go forms of `$fillable` and `$hidden`.
 - Validation: `lagoon.Validate` (where `required` fails on a zero date or time) accepts Laravel-style rule strings (`required`, `nullable`, `integer`, `numeric`, `between`, `min`, `max`, `in`, `unique`, `boolean`, `email`, `confirmed`, `different`, `mimes`) and returns a field-to-messages map, translated through phrasebook when a translator is given. Unknown rule tokens are an error. A failed numeric range reports the bound that failed: the `min` message below the lower bound, the `max` message above the upper one, and the numeric `between` message when the bound came from `between`.
-- Request validation: `lagoon.ValidateRequest` reproduces Laravel 9 request validation for ported API endpoints, so a 422 body matches the PHP one message for message. It takes the decoded input and an ordered `lagoon.RequestRule` table (attribute names may hold `*` wildcards, expanded against the input to `posts.0.title`), runs the rules of each attribute in order and stops an attribute after a failed implicit rule (`required`, `present`, `filled`, `accepted`) or, under `bail`, after any failure. A non-implicit rule is skipped for an absent attribute, a blank string, a null value under `nullable` and an absent key under `sometimes`. Supported rules: `required`, `present`, `filled`, `accepted`, `nullable`, `sometimes`, `bail`, `array`, `string`, `integer`, `numeric`, `boolean`, `email` (PHP `FILTER_VALIDATE_EMAIL`, WinterCMS's default), `url`, `date`, `after`, `after_or_equal`, `before`, `before_or_equal` (a date, a relative word such as `tomorrow`, or another field), `exists:table,column`, `regex`, `not_regex`, `in`, `not_in`, `file`, `image`, `mimes`, `min`, `max`, `size` and `between`, plus closure rules built with `lagoon.CustomRule`. The size rules compare the number under `numeric` or `integer` (exactly, as decimals), the element count of an array, kilobytes of a `lagoon.UploadedFile`, and otherwise the length in characters, and pick the matching message. Messages come from the `lagoon::validation` catalog in the request locale; `lagoon.ErrorKeys` gives the attribute order of PHP's message bag.
+- Request validation: `lagoon.ValidateRequest` reproduces Laravel 9 request validation for ported API endpoints, so a 422 body matches the PHP one message for message. It takes the decoded input and an ordered `lagoon.RequestRule` table (attribute names may hold `*` wildcards, expanded against the input to `posts.0.title`), runs the rules of each attribute in order and stops an attribute after a failed implicit rule (`required`, `present`, `filled`, `accepted`) or, under `bail`, after any failure. A non-implicit rule is skipped for an absent attribute, a blank string, a null value under `nullable` and an absent key under `sometimes`. Supported rules: `required`, `present`, `filled`, `accepted`, `nullable`, `sometimes`, `bail`, `array`, `string`, `integer`, `numeric`, `boolean`, `email` (PHP `FILTER_VALIDATE_EMAIL`, WinterCMS's default), `url`, `date`, `after`, `after_or_equal`, `before`, `before_or_equal` (a date, a relative word such as `tomorrow`, or another field), `exists:table,column`, `regex`, `not_regex`, `in`, `not_in`, `file`, `image`, `mimes`, `min`, `max`, `size`, `between` and `prohibited` (fails for any value `required` would accept, `0` and `false` included; not implicit, so an absent key, `null`, a blank string and an empty array pass, and with no catalog line its message is the key `validation.prohibited`), plus closure rules built with `lagoon.CustomRule`. The size rules compare the number under `numeric` or `integer` (exactly, as decimals), the element count of an array, kilobytes of a `lagoon.UploadedFile`, and otherwise the length in characters, and pick the matching message. Messages come from the `lagoon::validation` catalog in the request locale; `lagoon.ErrorKeys` gives the attribute order of PHP's message bag.
 - Safe ordering: `lagoon.OrderBy` appends an ORDER BY only for an allow-listed column and an `asc` or `desc` direction, and `lagoon.Collate` adds a validated `COLLATE` clause for language-specific text order (for example the ICU collation `pl-x-icu`); lagoon puts no requirement on the database's default locale.
 - Pagination: `lagoon.Paginate` builds a `lagoon.Page` with `data` and `meta` (`current_page`, `last_page`, `per_page`, `total`).
 - Date and time columns: `lagoon.Date` (a `DATE` column, JSON `"2026-10-02"`) and `lagoon.TimeOfDay` (a `TIME` column, JSON `"14:30:00"`) implement `sql.Scanner`, `driver.Valuer`, JSON and text marshalling, and store NULL for their zero value; `*lagoon.Date` and `*lagoon.TimeOfDay` are the nullable variants, next to `time.Time` and `*time.Time` for `timestamptz`. Build them with `lagoon.NewDate`, `lagoon.DateOf`, `lagoon.ParseDate`, `lagoon.NewTimeOfDay` and `lagoon.ParseTimeOfDay`. `lagoon.Fill` fills all six from JSON strings (RFC 3339 for `time.Time`) through their text unmarshalling, after every conversion it already made. Behaviour change: `required` now treats a zero `time.Time`, `lagoon.Date` or `lagoon.TimeOfDay` (or a pointer to one) as empty, so declare optional dates as pointer fields.