fix: include (not set) proxy type calls in standard and total counts (#714)

[saiflayouni]

Summary

• When proxy_deployment_type dimension returns (not set) values, those API calls were added to totalApiCalls but silently dropped from totalStandard, making them invisible in the --proxy-type billing report output
• EXTENSIBLE and STANDARD dimension calls also did not contribute to totalApiCalls, so the total count only reflected unclassified proxies when dimension mode was active
• Fixed by accumulating all dimension values (EXTENSIBLE, STANDARD, (not set)) into totalApiCalls, and also crediting (not set) calls to totalStandard (unclassified proxies are not extensible and should count as standard)

Fixes #714

Test plan

• Run apigeecli reports total-api-calls --proxy-type against an environment that has proxies with mixed or missing deployment types
• Verify the standard count now includes calls from proxies with (not set) deployment type
• Verify the total count matches extensible + standard

🤖 Generated with Claude Code

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