Add acronym expansion guidance to all agent prompts

Agents now spell out acronyms in full on first use (e.g. "Web Content
Accessibility Guidelines (WCAG)") for clarity. The instruction covers
common acronyms like WCAG, FSCS, GDE, APR, CTA, FCA, PRA, and T&Cs,
and applies to any acronym encountered in output.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/app/agents/brand_agent.py

@@ -153,6 +153,7 @@ If the proof is nonsensical, not a marketing material, or cannot be analyzed, se
   (a) Always capitalise the first word after a full stop, including labels like "Recommendation:" and "Issue:".
   (b) End every bullet point with a full stop if it is a complete sentence. If bullets are short fragments, omit the full stop — but be consistent within the same output.
   (c) Write "e.g." with no comma after it (e.g. "Apply rotation" not "e.g., Apply rotation").
+- IMPORTANT: Always spell out acronyms in full on first use, with the abbreviation in parentheses. Use the short form only for subsequent mentions within the same output. Common acronyms to expand include: WCAG (Web Content Accessibility Guidelines), FSCS (Financial Services Compensation Scheme), GDE (Global Digital Expression), APR (Annual Percentage Rate), CTA (Call-to-Action), FCA (Financial Conduct Authority), PRA (Prudential Regulation Authority), T&Cs (Terms and Conditions). Apply this rule to any acronym, not only those listed here.
 """
 
         # Determine if revision fields should be included

backend/app/agents/channel_best_practices_agent.py

@@ -146,6 +146,7 @@ If the proof is nonsensical, not a marketing material, or cannot be analyzed, se
   (a) Always capitalise the first word after a full stop, including labels like "Recommendation:" and "Issue:".
   (b) End every bullet point with a full stop if it is a complete sentence. If bullets are short fragments, omit the full stop — but be consistent within the same output.
   (c) Write "e.g." with no comma after it (e.g. "Apply rotation" not "e.g., Apply rotation").
+- IMPORTANT: Always spell out acronyms in full on first use, with the abbreviation in parentheses. Use the short form only for subsequent mentions within the same output. Common acronyms to expand include: WCAG (Web Content Accessibility Guidelines), FSCS (Financial Services Compensation Scheme), GDE (Global Digital Expression), APR (Annual Percentage Rate), CTA (Call-to-Action), FCA (Financial Conduct Authority), PRA (Prudential Regulation Authority), T&Cs (Terms and Conditions). Apply this rule to any acronym, not only those listed here.
 """
 
         # Determine if revision fields should be included

backend/app/agents/channel_tech_specs_agent.py

@@ -154,6 +154,7 @@ If the proof is nonsensical, not a marketing material, or cannot be analyzed, se
   (a) Always capitalise the first word after a full stop, including labels like "Recommendation:" and "Issue:".
   (b) End every bullet point with a full stop if it is a complete sentence. If bullets are short fragments, omit the full stop — but be consistent within the same output.
   (c) Write "e.g." with no comma after it (e.g. "Apply rotation" not "e.g., Apply rotation").
+- IMPORTANT: Always spell out acronyms in full on first use, with the abbreviation in parentheses. Use the short form only for subsequent mentions within the same output. Common acronyms to expand include: WCAG (Web Content Accessibility Guidelines), FSCS (Financial Services Compensation Scheme), GDE (Global Digital Expression), APR (Annual Percentage Rate), CTA (Call-to-Action), FCA (Financial Conduct Authority), PRA (Prudential Regulation Authority), T&Cs (Terms and Conditions). Apply this rule to any acronym, not only those listed here.
 """
 
         # Determine if revision fields should be included

backend/app/agents/lead_agent.py

@@ -154,6 +154,7 @@ Your summary should:
   (a) Always capitalise the first word after a full stop, including labels like "Recommendation:" and "Issue:".
   (b) End every bullet point with a full stop if it is a complete sentence. If bullets are short fragments, omit the full stop — but be consistent within the same output.
   (c) Write "e.g." with no comma after it (e.g. "Apply rotation" not "e.g., Apply rotation").
+- IMPORTANT: Always spell out acronyms in full on first use, with the abbreviation in parentheses. Use the short form only for subsequent mentions within the same output. Common acronyms to expand include: WCAG (Web Content Accessibility Guidelines), FSCS (Financial Services Compensation Scheme), GDE (Global Digital Expression), APR (Annual Percentage Rate), CTA (Call-to-Action), FCA (Financial Conduct Authority), PRA (Prudential Regulation Authority), T&Cs (Terms and Conditions). Apply this rule to any acronym, not only those listed here.
 {revision_context}
 Here are the specialist reviews:
 {self._format_reviews(reviews)}

backend/app/agents/legal_agent.py

@@ -156,6 +156,7 @@ If the proof is nonsensical, not a marketing material, or cannot be analyzed, se
   (a) Always capitalise the first word after a full stop, including labels like "Recommendation:" and "Issue:".
   (b) End every bullet point with a full stop if it is a complete sentence. If bullets are short fragments, omit the full stop — but be consistent within the same output.
   (c) Write "e.g." with no comma after it (e.g. "Apply rotation" not "e.g., Apply rotation").
+- IMPORTANT: Always spell out acronyms in full on first use, with the abbreviation in parentheses. Use the short form only for subsequent mentions within the same output. Common acronyms to expand include: WCAG (Web Content Accessibility Guidelines), FSCS (Financial Services Compensation Scheme), GDE (Global Digital Expression), APR (Annual Percentage Rate), CTA (Call-to-Action), FCA (Financial Conduct Authority), PRA (Prudential Regulation Authority), T&Cs (Terms and Conditions). Apply this rule to any acronym, not only those listed here.
 """
 
         # Determine if revision fields should be included