fix(tick): validate time and sym column types

[belowzeroff]

Summary

• validate that tick schemas start with time and sym columns of the expected q types
• reject timestamp time columns at startup instead of failing later on first update insert

Verification

• q tick.q sym -q with time:timespan starts and returns .u.t as ,`trade
• q tick.q sym -q with time:timestamp fails at startup with `timesym
• git diff --check