[BUG] Rich markup mangles bracketed table cell text (follow-up from #754: per-cell Text(value)) #757

Summary

The emoji-substitution half of the #754 root cause is fixed by disabling emoji at the
console level (Gerrit change 1255419), but markup=True is still active for table cell
strings. Every cell is parsed as Rich markup, so bracketed free text is silently dropped
or restyled instead of being rendered verbatim.

Observed with rich 14.3.2 and emoji=False:

"rack [h01] u01"            -> "rack  u01"      # [h01] eaten entirely
"vsan[b]x"                  -> "vsanx"
"alloc [red]urgent[/red]"   -> "alloc urgent"
"env [DEV] tier-1"          -> unchanged (unknown tag kept)

Where it is reachable

• quads --summary --detail: the Description column carries assignment descriptions
  (free text) through RichTable cells.
• The Detailed Report (src/quads/tools/reports.py), which renders the same descriptions
  into tables.

Any future table column holding user-controlled text (descriptions, rack/location,
tickets, ...) has the same exposure.

Expected

Cell values are rendered exactly as stored.

Suggested fix

Pass per-cell Text(value) renderables to add_row (or rich.markup.escape(value)) for
data columns, so markup and emoji parsing are both skipped. Text is a renderable, so
Text("04:32:01:ab:62:f1") and Text("rack [h01] u01") render verbatim. Console-level
emoji=False then remains useful for non-table output.

Context

Raised as the non-blocking follow-up in the review for #754 (Gerrit change 1255419) so
the markup half does not get lost with that change.