docs: show the real two-line shape of the withheld-variable log

The snippet put variable names on the summary line. Solo actually writes a
summary ending in "for that command:" and then one or more "withheld from
'<command>':" lines carrying the names, so a reader comparing the example to
their own log would not find a match.

Replaces it with output copied from a real run and explains that searching for a
variable name lands on the second line, which also identifies the command.

Related to hiero-ledger/solo#5895

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Signed-off-by: Jeffrey Tang <jeffrey@swirldslabs.com>

Author: JeffreyDallas

content/en/docs/advanced-solo-setup/subprocess-environment-filtering.md

@@ -41,13 +41,17 @@ Select-String -Path "$HOME\.solo\logs\solo.log" -Pattern "MY_VARIABLE"
 {{% /tab %}}
 {{< /tabpane >}}
 
-A withheld variable appears in a line like:
+Solo writes a summary line followed by one or more lines carrying the names, so your variable
+appears on a `withheld from` line rather than in the summary:
 
 ```text
-Withheld 83 environment variable(s) from 'helm' commands because they are not on the
-allowlist for that command: AI_AGENT, ..., MY_VARIABLE, ...
+[19:45:49.621] INFO: Withheld 83 environment variable(s) from 'helm' commands because they are not on the allowlist for that command:
+[19:45:49.621] INFO:   withheld from 'helm': AI_AGENT, APPLICATION_INSIGHTS_NO_STATSBEAT, ..., MY_VARIABLE, ...
 ```
 
+Searching for the variable name finds the second line, which also tells you which command withheld
+it. To see everything withheld from one command instead, search for `withheld from 'helm'`.
+
 This is logged at `info`, so it is present in the log by default — you do not need to re-run
 with `--debug`. It is emitted once per command type per run, and long lists are split across
 several lines so that every name remains searchable.