[pcbeingused333]

Description

AgeGraphProjectionApplier::flush_graph_mutations builds the list of endpoint ids for get_edges_for_nodes_batch by flat-mapping the source and target of every pending edge upsert. A node used by k edges therefore appears k times in the list. On the AGE path the query unnests that array and joins "EDGE" to it on both ends, so an edge between two repeated nodes comes back k_src * k_tgt times: on an entity-dense document the lookup result (and memory) grows with the square of the repetition instead of with the number of edges, which is the first half of #511.

The fix moves the collection into edge_upsert_endpoint_ids, which sorts and dedups the ids before the lookup, the same thing resolve_edge_deletes already does for the delete path. Behaviour for distinct ids is unchanged.

This only addresses the duplicate-id amplification. The missing retry ceiling in the projection worker (second half of the issue) is not touched here.

Refs #511

Type of change

• Bug fix
• New feature
• Breaking change
• Documentation update
• Other (describe below)

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing tests pass locally with my changes

Additional context

New edge_upsert_endpoint_tests in projection/appliers.rs: edges A-B, B-A, A-C and A-B with another relation must yield ["A", "B", "C"], plus the empty case. Without the sort/dedup the first test gets 8 ids back and fails; with it both pass (cargo test -p edgequake-storage --lib --features postgres edge_upsert_endpoint). rustfmt --check is clean and the crate builds with no new warnings.

This change was prepared with AI assistance (Claude Code).

[pcbeingused333]

Hi, friendly ping on this one when you have a moment. Happy to adjust anything or rebase if needed. Thanks for maintaining the project!