feat: add experimental apptainer backend

[dionhaefner]

Relevant issue or PR

n/a

Description of changes

Adds AppTainer as an alternative to Docker, which is more pervasive in HPC contexts.

Testing done

Some local tests (in a Linux VM on my ARM Mac) and new tests on CI, still needs verification on a real Linux machine

[codecov]

Codecov Report

❌ Patch coverage is 68.93287% with 361 lines in your changes missing coverage. Please review.
✅ Project coverage is 76.76%. Comparing base (1216135) to head (f8bf52b).

Files with missing lines	Patch %	Lines
tesseract_core/sdk/container_client/apptainer.py	63.16%	125 Missing and 40 partials ⚠️
tesseract_core/sdk/container_client/docker.py	71.11%	103 Missing and 44 partials ⚠️
tesseract_core/sdk/engine.py	75.00%	13 Missing and 13 partials ⚠️
tesseract_core/sdk/cli.py	41.93%	16 Missing and 2 partials ⚠️
tesseract_core/sdk/container_client/__init__.py	89.47%	1 Missing and 1 partial ⚠️
tesseract_core/sdk/container_client/exceptions.py	88.88%	2 Missing ⚠️
tesseract_core/sdk/container_client/base.py	95.65%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #654      +/-   ##
==========================================
- Coverage   78.09%   76.76%   -1.34%     
==========================================
  Files          39       44       +5     
  Lines        4721     5336     +615     
  Branches      775      867      +92     
==========================================
+ Hits         3687     4096     +409     
- Misses        724      876     +152     
- Partials      310      364      +54     

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[PasteurBot]

Benchmark Results

Benchmarks use a no-op Tesseract to measure pure framework overhead.

🚀 1 faster, ⚠️ 1 slower, ✅ 49 unchanged

Notable changes

Benchmark	Baseline	Current	Change	Status
cli/apply_1,000-apptainer	-	3618.286ms	new	🆕
cli/apply_1,000-docker	-	1758.073ms	new	🆕
cli/apply_100,000-apptainer	-	3631.594ms	new	🆕
cli/apply_100,000-docker	-	1764.382ms	new	🆕
cli/apply_10,000,000-apptainer	-	3668.416ms	new	🆕
cli/apply_10,000,000-docker	-	1836.404ms	new	🆕
decoding/base64_1,000	0.026ms	0.029ms	+12.4%	⚠️ slower
decoding/base64_100,000	0.794ms	0.683ms	-13.9%	🚀 faster
http/apply_1,000-apptainer	-	1.842ms	new	🆕
http/apply_100,000-apptainer	-	29.150ms	new	🆕
http/apply_10,000,000-apptainer	-	2938.966ms	new	🆕

Full results

Benchmark	Baseline	Current	Change	Status
api/apply_1,000	0.505ms	0.502ms	-0.6%	✅
api/apply_100,000	0.506ms	0.502ms	-0.9%	✅
api/apply_10,000,000	0.502ms	0.501ms	-0.3%	✅
cli/apply_1,000-apptainer	-	3618.286ms	new	🆕
cli/apply_1,000-docker	-	1758.073ms	new	🆕
cli/apply_100,000-apptainer	-	3631.594ms	new	🆕
cli/apply_100,000-docker	-	1764.382ms	new	🆕
cli/apply_10,000,000-apptainer	-	3668.416ms	new	🆕
cli/apply_10,000,000-docker	-	1836.404ms	new	🆕
decoding/base64_1,000	0.026ms	0.029ms	+12.4%	⚠️ slower
decoding/base64_100,000	0.794ms	0.683ms	-13.9%	🚀 faster
decoding/base64_10,000,000	68.039ms	67.316ms	-1.1%	✅
decoding/base64+lz4_1,000	0.031ms	0.031ms	-0.6%	✅
decoding/base64+lz4_100,000	0.857ms	0.855ms	-0.3%	✅
decoding/base64+lz4_10,000,000	84.268ms	84.347ms	+0.1%	✅
decoding/binref_1,000	0.185ms	0.183ms	-1.0%	✅
decoding/binref_100,000	0.233ms	0.231ms	-0.9%	✅
decoding/binref_10,000,000	9.223ms	9.134ms	-1.0%	✅
decoding/binref+lz4_1,000	0.191ms	0.188ms	-1.4%	✅
decoding/binref+lz4_100,000	0.303ms	0.293ms	-3.2%	✅
decoding/binref+lz4_10,000,000	26.416ms	26.310ms	-0.4%	✅
decoding/json_1,000	0.100ms	0.100ms	+0.3%	✅
decoding/json_100,000	9.352ms	9.339ms	-0.1%	✅
decoding/json_10,000,000	1103.920ms	1101.211ms	-0.2%	✅
encoding/base64_1,000	0.028ms	0.028ms	+1.1%	✅
encoding/base64_100,000	0.146ms	0.146ms	+0.1%	✅
encoding/base64_10,000,000	23.264ms	23.626ms	+1.6%	✅
encoding/base64+lz4_1,000	0.032ms	0.032ms	-0.2%	✅
encoding/base64+lz4_100,000	0.247ms	0.248ms	+0.2%	✅
encoding/base64+lz4_10,000,000	58.210ms	58.744ms	+0.9%	✅
encoding/binref_1,000	0.279ms	0.277ms	-0.7%	✅
encoding/binref_100,000	0.454ms	0.449ms	-1.2%	✅
encoding/binref_10,000,000	17.375ms	17.554ms	+1.0%	✅
encoding/binref+lz4_1,000	0.288ms	0.285ms	-1.2%	✅
encoding/binref+lz4_100,000	0.589ms	0.581ms	-1.4%	✅
encoding/binref+lz4_10,000,000	52.629ms	54.177ms	+2.9%	✅
encoding/json_1,000	0.141ms	0.141ms	-0.1%	✅
encoding/json_100,000	14.821ms	14.766ms	-0.4%	✅
encoding/json_10,000,000	1495.990ms	1494.854ms	-0.1%	✅
http/apply_1,000-apptainer	-	1.842ms	new	🆕
http/apply_1,000-docker	2.975ms	2.958ms	-0.6%	✅
http/apply_100,000-apptainer	-	29.150ms	new	🆕
http/apply_100,000-docker	8.966ms	8.960ms	-0.1%	✅
http/apply_10,000,000-apptainer	-	2938.966ms	new	🆕
http/apply_10,000,000-docker	674.588ms	681.150ms	+1.0%	✅
roundtrip/base64_1,000	0.059ms	0.059ms	-0.6%	✅
roundtrip/base64_100,000	0.779ms	0.727ms	-6.7%	✅
roundtrip/base64_10,000,000	90.495ms	90.982ms	+0.5%	✅
roundtrip/base64+lz4_1,000	0.064ms	0.066ms	+3.2%	✅
roundtrip/base64+lz4_100,000	0.958ms	0.954ms	-0.5%	✅
roundtrip/base64+lz4_10,000,000	142.824ms	143.296ms	+0.3%	✅
roundtrip/binref_1,000	0.479ms	0.478ms	-0.1%	✅
roundtrip/binref_100,000	0.695ms	0.696ms	+0.2%	✅
roundtrip/binref_10,000,000	26.768ms	27.012ms	+0.9%	✅
roundtrip/binref+lz4_1,000	0.496ms	0.493ms	-0.7%	✅
roundtrip/binref+lz4_100,000	0.911ms	0.901ms	-1.1%	✅
roundtrip/binref+lz4_10,000,000	79.662ms	80.616ms	+1.2%	✅
roundtrip/json_1,000	0.249ms	0.250ms	+0.7%	✅
roundtrip/json_100,000	21.689ms	22.093ms	+1.9%	✅
roundtrip/json_10,000,000	2599.198ms	2596.182ms	-0.1%	✅

• Runner: Linux 6.17.0-1020-azure x86_64