chore: add watchdog canister changelog

[maksymar]

This PR adds changelog file for a watchdog canister.

[github-actions[bot]]

canbench 🏋 (dir: .) 1a34cd6644ce951b6885c7026c1858e533871ed5 2025-07-24 12:34:19 UTC

✅ ./canbench_results.yml is up to date 📦 canbench_results_benchmark.csv available in artifacts

~/work/bitcoin-canister/bitcoin-canister/scripts ~/work/bitcoin-canister/bitcoin-canister
~/work/bitcoin-canister/bitcoin-canister
---------------------------------------------------

Benchmark: insert_300_blocks
  total:
    instructions: 506.99 M (-1.11%) (change within noise threshold)
    heap_increase: 10 pages (no change)
    stable_memory_increase: 0 pages (no change)

---------------------------------------------------

Benchmark: get_metrics
  total:
    instructions: 7.90 M (-0.00%) (change within noise threshold)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

---------------------------------------------------

Benchmark: insert_block_headers
  total:
    instructions: 3.17 B (0.00%) (change within noise threshold)
    heap_increase: 1 pages (no change)
    stable_memory_increase: 0 pages (no change)

---------------------------------------------------

Benchmark: insert_block_headers_multiple_times
  total:
    instructions: 11.69 B (0.00%) (change within noise threshold)
    heap_increase: 7 pages (no change)
    stable_memory_increase: 0 pages (no change)

---------------------------------------------------

Benchmark: pre_upgrade_with_many_unstable_blocks
  total:
    instructions: 5.99 B (0.00%) (change within noise threshold)
    heap_increase: 4097 pages (no change)
    stable_memory_increase: 1792 pages (no change)

  serialize_blocktree (scope):
    calls: 1 (no change)
    instructions: 2.40 B (no change)
    heap_increase: 2048 pages (no change)
    stable_memory_increase: 0 pages (no change)

  serialize_blocktree_flatten (scope):
    calls: 1 (no change)
    instructions: 183.80 K (no change)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

  serialize_blocktree_serialize_seq (scope):
    calls: 1 (no change)
    instructions: 2.40 B (no change)
    heap_increase: 2048 pages (no change)
    stable_memory_increase: 0 pages (no change)

---------------------------------------------------

Summary:
  instructions:
    status:   No significant changes 👍
    counts:   [total 5 | regressed 0 | improved 0 | new 0 | unchanged 5]
    change:   [max +14.00K | p75 +2.89K | median +1.40K | p25 -44 | min -5.67M]
    change %: [max 0.00% | p75 0.00% | median 0.00% | p25 -0.00% | min -1.11%]

  heap_increase:
    status:   No significant changes 👍
    counts:   [total 5 | regressed 0 | improved 0 | new 0 | unchanged 5]
    change:   [max 0 | p75 0 | median 0 | p25 0 | min 0]
    change %: [max 0.00% | p75 0.00% | median 0.00% | p25 0.00% | min 0.00%]

  stable_memory_increase:
    status:   No significant changes 👍
    counts:   [total 5 | regressed 0 | improved 0 | new 0 | unchanged 5]
    change:   [max 0 | p75 0 | median 0 | p25 0 | min 0]
    change %: [max 0.00% | p75 0.00% | median 0.00% | p25 0.00% | min 0.00%]

---------------------------------------------------
CSV results saved to canbench_results.csv

[mducroux]

Understanding: do you plan to add a changelog file for the bitcoin canister as well?

[maksymar]

Understanding: do you plan to add a changelog file for the bitcoin canister as well?

no, it was a leftover PR that I started some time ago. but I think it's valuable to have one, so I'd encourage you to do that based on watchdog canister changelog. what do you think?