feat: support block comments

[ilbertt]

Overview
Adds support for block comments that are "associated" to types, fields and services in Candid. "Associated" means that there's no empty line between the last line of the comment and the underlying type, field or service.

Requirements
#619 must be merged before this one

[github-actions]

Name	Max Mem (Kb)	Encode	Decode
blob	4_224	20_459_903	12_084_065
btreemap	75_456	4_641_551_699 ($\textcolor{red}{0.00\%}$)	15_347_627_594
nns	192	2_145_376 ($\textcolor{red}{0.00\%}$)	5_792_941 ($\textcolor{red}{0.40\%}$)
nns_list_proposal	1_216	8_062_642 ($\textcolor{red}{0.03\%}$)	84_424_449 ($\textcolor{green}{-0.00\%}$)
option_list	192	7_905_201 ($\textcolor{green}{-0.00\%}$)	27_478_042 ($\textcolor{green}{-0.29\%}$)
text	6_336	20_457_057	17_315_856
variant_list	192	7_898_808 ($\textcolor{red}{0.00\%}$)	25_657_946
vec_int16	16_704	168_585_203	1_159_749_481

• Parser cost: 18_067_353 ($\textcolor{green}{-0.10\%}$)
• Extra args: 3_494_935

Click to see raw report

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Benchmark: blob
  total:
    instructions: 32.55 M (no change)
    heap_increase: 66 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 20.46 M (no change)
    heap_increase: 66 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 12.08 M (no change)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

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

Benchmark: text
  total:
    instructions: 37.78 M (no change)
    heap_increase: 99 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 20.46 M (no change)
    heap_increase: 66 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 17.32 M (no change)
    heap_increase: 33 pages (no change)
    stable_memory_increase: 0 pages (no change)

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Benchmark: vec_int16
  total:
    instructions: 1.33 B (no change)
    heap_increase: 261 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 168.59 M (no change)
    heap_increase: 261 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 1.16 B (no change)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

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

Benchmark: btreemap
  total:
    instructions: 19.99 B (0.00%) (change within noise threshold)
    heap_increase: 1179 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 4.64 B (0.00%) (change within noise threshold)
    heap_increase: 159 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 15.35 B (no change)
    heap_increase: 1020 pages (no change)
    stable_memory_increase: 0 pages (no change)

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

Benchmark: option_list
  total:
    instructions: 35.39 M (-0.23%) (change within noise threshold)
    heap_increase: 3 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 7.91 M (-0.00%) (change within noise threshold)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 27.48 M (-0.29%) (change within noise threshold)
    heap_increase: 3 pages (no change)
    stable_memory_increase: 0 pages (no change)

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

Benchmark: variant_list
  total:
    instructions: 33.56 M (0.00%) (change within noise threshold)
    heap_increase: 3 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 7.90 M (0.00%) (change within noise threshold)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 25.66 M (no change)
    heap_increase: 3 pages (no change)
    stable_memory_increase: 0 pages (no change)

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

Benchmark: nns
  total:
    instructions: 26.86 M (0.02%) (change within noise threshold)
    heap_increase: 3 pages (no change)
    stable_memory_increase: 0 pages (no change)

  0. Parsing (scope):
    calls: 1 (no change)
    instructions: 18.07 M (-0.10%) (change within noise threshold)
    heap_increase: 3 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 2.15 M (0.00%) (change within noise threshold)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 5.79 M (0.40%) (change within noise threshold)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

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

Benchmark: nns_list_proposal
  total:
    instructions: 92.49 M (0.00%) (change within noise threshold)
    heap_increase: 19 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 8.06 M (0.03%) (change within noise threshold)
    heap_increase: 5 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 84.42 M (-0.00%) (change within noise threshold)
    heap_increase: 14 pages (no change)
    stable_memory_increase: 0 pages (no change)

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

Benchmark: extra_args
  total:
    instructions: 3.49 M (no change)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

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

Summary:
  instructions:
    status:   No significant changes 👍
    counts:   [total 9 | regressed 0 | improved 0 | new 0 | unchanged 9]
    change:   [max +4.59K | p75 +51 | median 0 | p25 0 | min -80.24K]
    change %: [max +0.02% | p75 0.00% | median 0.00% | p25 0.00% | min -0.23%]

  heap_increase:
    status:   No significant changes 👍
    counts:   [total 9 | regressed 0 | improved 0 | new 0 | unchanged 9]
    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 9 | regressed 0 | improved 0 | new 0 | unchanged 9]
    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%]

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Successfully persisted results to canbench_results.yml