Crash on ALTER ... add column ... text

Bug Description:

mysql> drop table if exists t; create table t; insert into t values(1); flush ramchunk t; alter table t add column f2 text;
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drop table if exists t
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Query OK, 0 rows affected (0.03 sec)

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create table t
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Query OK, 0 rows affected (0.00 sec)

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insert into t values(1)
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Query OK, 1 row affected (0.00 sec)

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flush ramchunk t
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Query OK, 0 rows affected (0.01 sec)

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alter table t add column f2 text
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ERROR 2013 (HY000): Lost connection to MySQL server during query

Notes:

crashes in 6.3.6 too
alter table t add column f2 int doesn't lead to a crash.

Manticore Search Version:

Manticore 6.3.7 9987798ac@24101806 dev (columnar 2.3.1 30ad2d6@24100914) (secondary 2.3.1 30ad2d6@24100914) (knn 2.3.1 30ad2d6@24100914)

Operating System Version:

Ubuntu Jammy (dev2)

Have you tried the latest development version?

Internal Checklist:

^{To be completed by the assignee. Check off tasks that have been completed or are not applicable.}

- [x] Implementation completed - [x] Tests developed - [x] Documentation updated - [x] Documentation reviewed - [x] [Changelog](https://docs.google.com/spreadsheets/d/1mz_3dRWKs86FjRF7EIZUziUDK_2Hvhd97G0pLpxo05s/edit?pli=1&gid=1102439133) updated

manticoresoftware / manticoresearch