[clockdev]

Flow filters and URL macros can now use arbitrary named query parameters, such as brand or sub_id_30.

Filters use param:NAME, and URL templates use {param:NAME}. Macro values are percent-encoded. Built-in fields and macros retain their existing behavior.

The flow editor includes a Query parameter option and a parameter name input, with English and Russian translations. Invalid names are rejected, and submitted filter values are preserved when validation fails.

Parameter names support 1–64 ASCII letters, digits, underscores, and hyphens, starting with a letter or underscore. Values are limited to 2048 bytes; control characters and non-string values are rejected. Empty strings and 0 remain valid values.

No database migration or new dependency is required.

Validation:

• Unit, integration, and architecture regression: 807 passed, 4 skipped.
• Targeted browser tests passed.
• Targeted PHPStan and PHP syntax checks passed.
• Three GeoLookup tests were skipped because GeoLite2 databases were unavailable.
• One PostbackOutbox test was skipped because its local HTTP fixture prerequisite was unavailable.