feat(website): rename AA mutations to AA substitutions on details page

[anna-parker]

Alternative to #6135 - as discussed on slack https://loculus.slack.com/archives/C061ZQQM3N1/p1773419507020499 for consistency across organisms we will change the details page header amino acid mutations to amino acid substitutions

Screenshot

PR Checklist

• All necessary documentation has been adapted.
• The implemented feature is covered by appropriate, automated tests.
• Any manual testing that has been done is documented (i.e. what exactly was tested?)

🚀 Preview: https://rename-header.loculus.org

[claude]

Claude finished @anna-parker's task in 1m 2s —— View job

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Code Review

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The rename from "amino acid mutations" → "amino acid substitutions" is straightforward and the changes are generally clean. However, there is one significant bug introduced by this PR.

Bug: AA substitutions section will not render

DataTable.tsx, line 58:

const mutationSections = dataTableData.table.filter(({ header }) => header.toLowerCase().includes('mutation'));

DEFAULT_AA_MUTATION_DETAILS_HEADER is now 'Amino acid substitutions', which does not contain the word 'mutation'. At the same time, the generalSections filter correctly excludes it via explicit constant comparison (line 54–55). The net result is that rows with the AA substitutions header are excluded from both generalSections and mutationSections, so the entire amino acid substitutions panel will silently disappear from the details page.

The fix is to use the constants directly instead of a string match:

const mutationSections = dataTableData.table.filter(
    ({ header }) =>
        header === DEFAULT_NUC_MUTATION_DETAILS_HEADER || header === DEFAULT_AA_MUTATION_DETAILS_HEADER,
);

Fix this →

Minor: inconsistent terminology in search docs

DisplaySearchDocs.tsx, line 76 — the section heading was updated but the body text still reads:

"An amino acid mutation has the format…"

Since the heading now says "Amino acid substitutions and insertions", this paragraph body should say "substitution" too for consistency.

[tombch]

Looks good! Although one issue I've spotted is under the 'Amino acid substitutions' it says 'mutations called relative to the...':

[tombch]

Looks good to me!